INVESTMENT SECURITIES AND OTHER SECURITIES - Schedule of Amortized Cost, Fair Value, and Gross Unrealized Gains and Losses (Details) - USD ($)
|
Jun. 30, 2019 |
Dec. 31, 2018 |
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
$ 13,668,000,000
|
$ 14,108,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
109,000,000
|
31,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |
82,000,000
|
359,000,000
|
| Debt Securities, Available-for-sale |
13,695,000,000
|
13,780,000,000
|
| Debt Securities, Held-to-maturity |
8,704,000,000
|
8,565,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain |
75,000,000
|
2,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss |
(31,000,000)
|
(281,000,000)
|
| Debt Securities, Held-to-maturity, Fair Value |
8,748,000,000
|
8,286,000,000
|
| Equity Securities, FV-NI, Cost |
440,000,000
|
564,000,000
|
| Equity Securities, FV-NI, Accumulated Gross Unrealized Gain, before Tax |
0
|
1,000,000
|
| Equity Securities, FV-NI, Accumulated Gross Unrealized Loss, before Tax |
0
|
0
|
| Equity Securities, FV-NI |
440,000,000
|
565,000,000
|
| US Treasury Securities [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
11,000,000
|
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 |
11,000,000
|
5,000,000
|
| Collateralized Mortgage Obligations [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
6,431,000,000
|
7,185,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
53,000,000
|
15,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |
26,000,000
|
201,000,000
|
| Debt Securities, Available-for-sale |
6,458,000,000
|
6,999,000,000
|
| Debt Securities, Held-to-maturity |
2,072,000,000
|
2,124,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain |
30,000,000
|
0
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss |
(4,000,000)
|
(47,000,000)
|
| Debt Securities, Held-to-maturity, Fair Value |
2,098,000,000
|
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 |
1,853,000,000
|
1,261,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
28,000,000
|
9,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |
1,000,000
|
15,000,000
|
| Debt Securities, Available-for-sale |
1,880,000,000
|
1,255,000,000
|
| Debt Securities, Held-to-maturity |
2,153,000,000
|
1,851,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain |
28,000,000
|
2,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss |
0
|
(42,000,000)
|
| Debt Securities, Held-to-maturity, Fair Value |
2,181,000,000
|
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 |
1,476,000,000
|
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 |
16,000,000
|
58,000,000
|
| Debt Securities, Available-for-sale |
1,460,000,000
|
1,583,000,000
|
| Debt Securities, Held-to-maturity |
4,147,000,000
|
4,235,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain |
13,000,000
|
0
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss |
(27,000,000)
|
(186,000,000)
|
| Debt Securities, Held-to-maturity, Fair Value |
4,133,000,000
|
4,049,000,000
|
| Other Federal Agencies [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
114,000,000
|
128,000,000
|
| 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
|
2,000,000
|
| Debt Securities, Available-for-sale |
115,000,000
|
126,000,000
|
| Debt Securities, Held-to-maturity |
328,000,000
|
350,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain |
4,000,000
|
0
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss |
0
|
(6,000,000)
|
| Debt Securities, Held-to-maturity, Fair Value |
332,000,000
|
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 |
9,885,000,000
|
10,220,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
82,000,000
|
24,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |
43,000,000
|
276,000,000
|
| Debt Securities, Available-for-sale |
9,924,000,000
|
9,968,000,000
|
| Debt Securities, Held-to-maturity |
8,700,000,000
|
8,560,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain |
75,000,000
|
2,000,000
|
| Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss |
(31,000,000)
|
(281,000,000)
|
| Debt Securities, Held-to-maturity, Fair Value |
8,744,000,000
|
8,281,000,000
|
| Municipal securities |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
3,280,000,000
|
3,512,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
18,000,000
|
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 |
3,260,000,000
|
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 |
448,000,000
|
318,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |
8,000,000
|
1,000,000
|
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |
1,000,000
|
4,000,000
|
| Debt Securities, Available-for-sale |
455,000,000
|
315,000,000
|
| Corporate Debt Securities [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
50,000,000
|
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 |
51,000,000
|
53,000,000
|
| Other Securities [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Debt Securities, Available-for-sale, Amortized Cost |
5,000,000
|
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 |
5,000,000
|
4,000,000
|
| Mutual Fund [Member] |
|
|
| Schedule of investment securities and other securities [Line Items] |
|
|
| Equity Securities, FV-NI, Cost |
13,000,000
|
20,000,000
|
| Equity Securities, FV-NI, Accumulated Gross Unrealized Gain, before Tax |
(1,000,000)
|
0
|
| Equity Securities, FV-NI, Accumulated Gross Unrealized Loss, before Tax |
0
|
0
|
| Equity Securities, FV-NI |
12,000,000
|
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 |
130,000,000
|
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 |
130,000,000
|
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
|