INVESTMENT SECURITIES AND OTHER SECURITIES - Schedule of Amortized Cost, Fair Value, and Gross Unrealized Gains and Losses (Details) - USD ($)
|
Mar. 31, 2019 |
Dec. 31, 2018 |
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
$ 14,126,000,000
|
$ 14,108,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
64,000,000
|
31,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |
208,000,000
|
359,000,000
|
| Debt Securities, Available-for-sale |
13,982,000,000
|
13,780,000,000
|
| Debt Securities, Held-to-maturity |
8,747,000,000
|
8,565,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain |
16,000,000
|
2,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss |
(172,000,000)
|
(281,000,000)
|
| Debt Securities, Held-to-maturity, Fair Value |
8,591,000,000
|
8,286,000,000
|
| Equity Securities, FV-NI, Cost |
485,000,000
|
564,000,000
|
| Equity Securities, FV-NI, Accumulated Gross Unrealized Gain, before Tax |
1,000,000
|
1,000,000
|
| Equity Securities, FV-NI, Accumulated Gross Unrealized Loss, before Tax |
0
|
0
|
| Equity Securities, FV-NI |
486,000,000
|
565,000,000
|
| US Treasury Securities [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
5,000,000
|
5,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
0
|
0
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |
0
|
0
|
| Debt Securities, Available-for-sale |
5,000,000
|
5,000,000
|
| Collateralized Mortgage Obligations [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
7,093,000,000
|
7,185,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
25,000,000
|
15,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |
108,000,000
|
201,000,000
|
| Debt Securities, Available-for-sale |
7,010,000,000
|
6,999,000,000
|
| Debt Securities, Held-to-maturity |
2,125,000,000
|
2,124,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain |
4,000,000
|
0
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss |
(23,000,000)
|
(47,000,000)
|
| Debt Securities, Held-to-maturity, Fair Value |
2,106,000,000
|
2,077,000,000
|
| Residential Mortgage Backed Securities [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
1,359,000,000
|
1,261,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
19,000,000
|
9,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |
5,000,000
|
15,000,000
|
| Debt Securities, Available-for-sale |
1,373,000,000
|
1,255,000,000
|
| Debt Securities, Held-to-maturity |
2,093,000,000
|
1,851,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain |
11,000,000
|
2,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss |
(15,000,000)
|
(42,000,000)
|
| Debt Securities, Held-to-maturity, Fair Value |
2,089,000,000
|
1,811,000,000
|
| Commercial Mortgage Backed Securities [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
1,606,000,000
|
1,641,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
0
|
0
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |
53,000,000
|
58,000,000
|
| Debt Securities, Available-for-sale |
1,553,000,000
|
1,583,000,000
|
| Debt Securities, Held-to-maturity |
4,187,000,000
|
4,235,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain |
1,000,000
|
0
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss |
(130,000,000)
|
(186,000,000)
|
| Debt Securities, Held-to-maturity, Fair Value |
4,058,000,000
|
4,049,000,000
|
| Other Federal Agencies [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
119,000,000
|
128,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
0
|
0
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |
1,000,000
|
2,000,000
|
| Debt Securities, Available-for-sale |
118,000,000
|
126,000,000
|
| Debt Securities, Held-to-maturity |
338,000,000
|
350,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain |
0
|
0
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss |
(4,000,000)
|
(6,000,000)
|
| Debt Securities, Held-to-maturity, Fair Value |
334,000,000
|
344,000,000
|
| US Government-sponsored Enterprises Debt Securities [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
10,182,000,000
|
10,220,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
44,000,000
|
24,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |
167,000,000
|
276,000,000
|
| Debt Securities, Available-for-sale |
10,059,000,000
|
9,968,000,000
|
| Debt Securities, Held-to-maturity |
8,743,000,000
|
8,560,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain |
16,000,000
|
2,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss |
(172,000,000)
|
(281,000,000)
|
| Debt Securities, Held-to-maturity, Fair Value |
8,587,000,000
|
8,281,000,000
|
| Municipal securities |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
3,539,000,000
|
3,512,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
17,000,000
|
6,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |
38,000,000
|
78,000,000
|
| Debt Securities, Available-for-sale |
3,518,000,000
|
3,440,000,000
|
| Debt Securities, Held-to-maturity |
4,000,000
|
5,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain |
0
|
0
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss |
0
|
0
|
| Debt Securities, Held-to-maturity, Fair Value |
4,000,000
|
5,000,000
|
| Asset-backed Securities [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
350,000,000
|
318,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
2,000,000
|
1,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |
3,000,000
|
4,000,000
|
| Debt Securities, Available-for-sale |
349,000,000
|
315,000,000
|
| Corporate Debt Securities [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
51,000,000
|
54,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
1,000,000
|
0
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |
0
|
1,000,000
|
| Debt Securities, Available-for-sale |
52,000,000
|
53,000,000
|
| Other Securities [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
4,000,000
|
4,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
0
|
0
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |
0
|
0
|
| Debt Securities, Available-for-sale |
4,000,000
|
4,000,000
|
| Mutual Fund [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Equity Securities, FV-NI, Cost |
21,000,000
|
20,000,000
|
| Equity Securities, FV-NI, Accumulated Gross Unrealized Gain, before Tax |
0
|
0
|
| Equity Securities, FV-NI, Accumulated Gross Unrealized Loss, before Tax |
0
|
0
|
| Equity Securities, FV-NI |
21,000,000
|
20,000,000
|
| Equity Securities [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Equity Securities, FV-NI, Cost |
1,000,000
|
1,000,000
|
| Equity Securities, FV-NI, Accumulated Gross Unrealized Gain, before Tax |
1,000,000
|
1,000,000
|
| Equity Securities, FV-NI, Accumulated Gross Unrealized Loss, before Tax |
0
|
0
|
| Equity Securities, FV-NI |
2,000,000
|
2,000,000
|
| Investment in Federal Home Loan Bank Stock [Member] | Nonmarketable Equity Securities [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Equity Securities, FV-NI, Cost |
167,000,000
|
248,000,000
|
| Equity Securities, FV-NI, Accumulated Gross Unrealized Gain, before Tax |
0
|
0
|
| Equity Securities, FV-NI, Accumulated Gross Unrealized Loss, before Tax |
0
|
0
|
| Equity Securities, FV-NI |
167,000,000
|
248,000,000
|
| Investment in Federal Reserve Stock [Member] | Nonmarketable Equity Securities [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Equity Securities, FV-NI, Cost |
296,000,000
|
295,000,000
|
| Equity Securities, FV-NI, Accumulated Gross Unrealized Gain, before Tax |
0
|
0
|
| Equity Securities, FV-NI, Accumulated Gross Unrealized Loss, before Tax |
0
|
0
|
| Equity Securities, FV-NI |
$ 296,000,000
|
$ 295,000,000
|