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v3.3.1.900

Investment Securities (Amortized Cost and Estimated Fair Value) (Details) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | ---
Held-to-maturity securities |  |
Amortized Cost | $ 2,400 | $ 2,400
Estimated Fair Value | 2,400 | 2,400
Carrying Value | 2,400 | 2,400
Available-for-sale securities |  |
Amortized Cost | 4,196,034 | 4,894,428
Gross unrealized gains | 50,165 | 68,516
Gross unrealized losses | (46,827) | (50,981)
Total investment securities | 4,199,372 | 4,911,963
Assets/Liabilities Measured at Fair Value |  |
Available-for-sale securities |  |
Total investment securities | 4,199,372 | 4,911,963
Carrying Value |  |
Available-for-sale securities |  |
Total investment securities | 4,199,372 | 4,911,963
Other securities |  |
Held-to-maturity securities |  |
Amortized Cost | 2,400 | 2,400
Estimated Fair Value | 2,400 | 2,400
Carrying Value | 2,400 | 2,400
Residential mortgage-backed securities |  |
Available-for-sale securities |  |
Amortized Cost | 3,908,809 | 4,597,590
Gross unrealized gains | 30,959 | 47,960
Gross unrealized losses | (46,557) | (45,178)
Residential mortgage-backed securities | Assets/Liabilities Measured at Fair Value |  |
Available-for-sale securities |  |
Total investment securities | 3,893,211 | 4,600,372
Residential mortgage-backed securities | Carrying Value |  |
Available-for-sale securities |  |
Total investment securities | 3,893,211 | 4,600,372
Mortgage-backed securities by Ginnie Mae |  |
Available-for-sale securities |  |
Total investment securities | 1,147,143 | 1,503,774
Mortgage-backed securities by Fannie Mae and Freddie Mac |  |
Available-for-sale securities |  |
Total investment securities | 2,724,839 | 3,072,535
Mortgage-backed securities by non-government entities |  |
Available-for-sale securities |  |
Total investment securities | 21,229 | 24,063
States and political subdivisions |  |
Available-for-sale securities |  |
Amortized Cost | 259,150 | 268,763
Gross unrealized gains | 18,579 | 19,131
Gross unrealized losses | (25) | (5,618)
States and political subdivisions | Assets/Liabilities Measured at Fair Value |  |
Available-for-sale securities |  |
Total investment securities | 277,704 | 282,276
States and political subdivisions | Carrying Value |  |
Available-for-sale securities |  |
Total investment securities | 277,704 | 282,276
Other |  |
Available-for-sale securities |  |
Amortized Cost | 28,075 | 28,075
Gross unrealized gains | 627 | 1,425
Gross unrealized losses | (245) | (185)
Other | Assets/Liabilities Measured at Fair Value |  |
Available-for-sale securities |  |
Total investment securities | 28,457 | 29,315
Other | Carrying Value |  |
Available-for-sale securities |  |
Total investment securities | $ 28,457 | $ 29,315

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