|
Held-to-Maturity Securities (Details) (USD $)
In Thousands, unless otherwise specified
|
Jun. 30, 2014
|
Dec. 31, 2013
|
| Contractual maturities of held-to-maturity securities |
|
|
| Held-to-maturity securities, Total |
$ 3,621,995
|
$ 3,836,667
|
| Held-to-maturity Securities, Fair Value |
3,611,261
|
3,760,898
|
| Amortized cost, gross unrealized gains and losses, and fair value by investment category |
|
|
| Held-to-maturity securities, Total |
3,621,995
|
3,836,667
|
| Held-to-maturity Securities, Gross Gain |
(23,566)
|
(6,349)
|
| Held-to-maturity Securities, Gross Losses |
34,300
|
82,118
|
| Held-to-maturity securities, fair value |
3,611,261
|
3,760,898
|
| Continuous Unrealized Loss Position |
|
|
| Total Temporarily Impaired Securities, Less Than Twelve Months, Fair Value |
1,199,903
|
3,001,774
|
| Total Temporarily Impaired Securities Unrealized Losses, Less Than Twelve Months, Fair Value |
(12,763)
|
(79,766)
|
| Total Temporarily Impaired Securities, Over Twelve Months, Fair Value |
648,172
|
22,548
|
| Total Temporarily Impaired Securites, Unrealized Losses Over Twelve Months |
(21,537)
|
(2,352)
|
| Total Temporarily Impaired Securities, Fair Value |
1,848,075
|
3,024,322
|
| Total Temporarily Impaired Securities, Unrealized Losses |
(34,300)
|
(82,118)
|
|
Federal agencies - mortgage backed securities [Member]
|
|
|
| Contractual maturities of held-to-maturity securities |
|
|
| Held-to-maturity Securities, Under 1 year |
0
|
0
|
| Held-to-maturity Securities, 1-5 years |
0
|
0
|
| Held-to-maturity Securities, 6-10 years |
24,901
|
24,901
|
| Held-to-maturity Securities, Over 10 years |
3,368,697
|
3,574,156
|
| Held-to-maturity securities, Total |
3,393,598
|
3,599,057
|
| Fair Value, Under 1 year |
0
|
0
|
| Fair Value, 1-5 years |
0
|
0
|
| Fair Value, 6-10 years |
23,780
|
22,549
|
| Fair Value, Over 10 years |
3,360,926
|
3,506,018
|
| Held-to-maturity Securities, Fair Value |
3,384,706
|
3,528,567
|
| Amortized cost, gross unrealized gains and losses, and fair value by investment category |
|
|
| Held-to-maturity securities, Total |
3,393,598
|
3,599,057
|
| Held-to-maturity Securities, Gross Gain |
(22,638)
|
(5,573)
|
| Held-to-maturity Securities, Gross Losses |
31,530
|
76,063
|
| Held-to-maturity securities, fair value |
3,384,706
|
3,528,567
|
| Continuous Unrealized Loss Position |
|
|
| Total Temporarily Impaired Securities, Less Than Twelve Months, Fair Value |
1,172,741
|
2,849,198
|
| Total Temporarily Impaired Securities Unrealized Losses, Less Than Twelve Months, Fair Value |
(12,372)
|
(73,711)
|
| Total Temporarily Impaired Securities, Over Twelve Months, Fair Value |
574,627
|
22,548
|
| Total Temporarily Impaired Securites, Unrealized Losses Over Twelve Months |
(19,158)
|
(2,352)
|
| Total Temporarily Impaired Securities, Fair Value |
1,747,368
|
2,871,746
|
| Total Temporarily Impaired Securities, Unrealized Losses |
(31,530)
|
(76,063)
|
|
Other Federal Agencies [Member]
|
|
|
| Contractual maturities of held-to-maturity securities |
|
|
| Held-to-maturity Securities, Under 1 year |
0
|
0
|
| Held-to-maturity Securities, 1-5 years |
0
|
0
|
| Held-to-maturity Securities, 6-10 years |
56,674
|
38,588
|
| Held-to-maturity Securities, Over 10 years |
163,068
|
189,999
|
| Held-to-maturity securities, Total |
219,742
|
228,587
|
| Fair Value, Under 1 year |
0
|
0
|
| Fair Value, 1-5 years |
0
|
0
|
| Fair Value, 6-10 years |
57,331
|
39,075
|
| Fair Value, Over 10 years |
160,911
|
185,097
|
| Held-to-maturity Securities, Fair Value |
218,242
|
224,172
|
| Amortized cost, gross unrealized gains and losses, and fair value by investment category |
|
|
| Held-to-maturity securities, Total |
219,742
|
228,587
|
| Held-to-maturity Securities, Gross Gain |
(928)
|
(776)
|
| Held-to-maturity Securities, Gross Losses |
(2,428)
|
(5,191)
|
| Held-to-maturity securities, fair value |
218,242
|
224,172
|
| Continuous Unrealized Loss Position |
|
|
| Total Temporarily Impaired Securities, Less Than Twelve Months, Fair Value |
18,849
|
144,417
|
| Total Temporarily Impaired Securities Unrealized Losses, Less Than Twelve Months, Fair Value |
(49)
|
(5,191)
|
| Total Temporarily Impaired Securities, Over Twelve Months, Fair Value |
73,545
|
0
|
| Total Temporarily Impaired Securites, Unrealized Losses Over Twelve Months |
(2,379)
|
0
|
| Total Temporarily Impaired Securities, Fair Value |
92,394
|
144,417
|
| Total Temporarily Impaired Securities, Unrealized Losses |
(2,428)
|
(5,191)
|
|
Municipal securities [Member]
|
|
|
| Contractual maturities of held-to-maturity securities |
|
|
| Held-to-maturity Securities, Under 1 year |
0
|
0
|
| Held-to-maturity Securities, 1-5 years |
0
|
0
|
| Held-to-maturity Securities, 6-10 years |
0
|
0
|
| Held-to-maturity Securities, Over 10 years |
8,655
|
9,023
|
| Held-to-maturity securities, Total |
8,655
|
9,023
|
| Fair Value, Under 1 year |
0
|
0
|
| Fair Value, 1-5 years |
0
|
0
|
| Fair Value, 6-10 years |
0
|
0
|
| Fair Value, Over 10 years |
8,313
|
8,159
|
| Held-to-maturity Securities, Fair Value |
8,313
|
8,159
|
| Amortized cost, gross unrealized gains and losses, and fair value by investment category |
|
|
| Held-to-maturity securities, Total |
8,655
|
9,023
|
| Held-to-maturity Securities, Gross Gain |
0
|
0
|
| Held-to-maturity Securities, Gross Losses |
(342)
|
(864)
|
| Held-to-maturity securities, fair value |
8,313
|
8,159
|
| Continuous Unrealized Loss Position |
|
|
| Total Temporarily Impaired Securities, Less Than Twelve Months, Fair Value |
8,313
|
8,159
|
| Total Temporarily Impaired Securities Unrealized Losses, Less Than Twelve Months, Fair Value |
(342)
|
(864)
|
| Total Temporarily Impaired Securities, Over Twelve Months, Fair Value |
0
|
0
|
| Total Temporarily Impaired Securites, Unrealized Losses Over Twelve Months |
0
|
0
|
| Total Temporarily Impaired Securities, Fair Value |
8,313
|
8,159
|
| Total Temporarily Impaired Securities, Unrealized Losses |
(342)
|
(864)
|
|
Total U.S. Government backed agencies [Member]
|
|
|
| Contractual maturities of held-to-maturity securities |
|
|
| Held-to-maturity securities, Total |
3,613,340
|
3,827,644
|
| Held-to-maturity Securities, Fair Value |
3,602,948
|
3,752,739
|
| Amortized cost, gross unrealized gains and losses, and fair value by investment category |
|
|
| Held-to-maturity securities, Total |
3,613,340
|
3,827,644
|
| Held-to-maturity Securities, Gross Gain |
(23,566)
|
(6,349)
|
| Held-to-maturity Securities, Gross Losses |
33,958
|
81,254
|
| Held-to-maturity securities, fair value |
3,602,948
|
3,752,739
|
| Continuous Unrealized Loss Position |
|
|
| Total Temporarily Impaired Securities, Less Than Twelve Months, Fair Value |
1,191,590
|
2,993,615
|
| Total Temporarily Impaired Securities Unrealized Losses, Less Than Twelve Months, Fair Value |
(12,421)
|
(78,902)
|
| Total Temporarily Impaired Securities, Over Twelve Months, Fair Value |
648,172
|
22,548
|
| Total Temporarily Impaired Securites, Unrealized Losses Over Twelve Months |
(21,537)
|
(2,352)
|
| Total Temporarily Impaired Securities, Fair Value |
1,839,762
|
3,016,163
|
| Total Temporarily Impaired Securities, Unrealized Losses |
$ (33,958)
|
$ (81,254)
|