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v3.19.1

Available for Sale Securities (Details) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 USD ($) | Mar. 31, 2018 USD ($) | Dec. 31, 2018 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost | $ 9,027,806 |  | $ 8,952,391
Available for sale securities | 9,025,198 |  | 8,857,120
Available-for-sale Securities, Gross Unrealized Gain | 66,888 |  | 42,986
Available-for-sale Securities, Gross Unrealized Loss | (69,496) |  | (138,257)
Pledged Assets Separately Reported, Securities Pledged as Collateral, at Fair Value | 10,300,000 |  | $ 9,100,000
Debt Securities, Available-for-sale, Realized Gain (Loss) [Abstract] |  |  |
Proceeds from sales of available for sale securities | 245,259 | $ 44,790 |
Available-for-sale Securities, Gross realized gains | 5,298 | 193 |
Available-for-sale Securities, Gross realized losses | (5,222) | (483) |
Available-for-sale Securities, Related federal and state income tax expense | $ 19 | $ (74) |
Available-for-sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 415 |  | 490
Debt Securities, Available-for-sale, Unrealized Loss Position [Abstract] |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 732,623 |  | $ 700,064
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 4,843,129 |  | 5,631,803
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value | 5,575,752 |  | 6,331,867
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses [Abstract] |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 1,849 |  | 1,615
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 67,647 |  | 136,642
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | 69,496 |  | 138,257
Fixed Maturity Securities [Member] |  |  |
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |  |
Available-for-sale Securities, Debt Maturities, Less than One Year, Amortized Cost Basis | 94,933 |  |
Available-for-sale Securities, Debt Maturities, One to Five Years, Amortized Cost Basis | 983,438 |  |
Available-for-sale Securities, Debt Maturities, Six To Ten Years, Amortized Cost Basis | 1,467,481 |  |
Available-for-sale Securities, Debt Maturities, Over Ten Years, Amortized Cost Basis | 391,939 |  |
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Amortized Cost | 2,937,791 |  |
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |  |
Available-for-sale Securities, Debt Maturities, Less than One Year, Fair Value | 94,398 |  |
Available-for-sale Securities, Debt Maturities, One to Five Years, Fair Value | 976,737 |  |
Available-for-sale Securities, Debt Maturities, Six to Ten Years, Fair Value | 1,473,499 |  |
Available-for-sale Securities, Debt Maturities, Over Ten Years, Fair Value | 392,520 |  |
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Fair Value | $ 2,937,154 |  |
Available-for-sale Securities, Debt Maturities, Weighted Average Maturity | 7.30 |  |
U.S. Treasury [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost | $ 1,880 |  | 496
Available for sale securities | 1,878 |  | 493
Available-for-sale Securities, Gross Unrealized Gain | 0 |  | 0
Available-for-sale Securities, Gross Unrealized Loss | $ (2) |  | $ (3)
Available-for-sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 1 |  | 1
Debt Securities, Available-for-sale, Unrealized Loss Position [Abstract] |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 0 |  | $ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 495 |  | 493
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value | 495 |  | 493
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses [Abstract] |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 |  | 0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 2 |  | 3
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | 2 |  | 3
Municipal and other tax-exempt securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost | 2,365 |  | 2,782
Available for sale securities | 2,447 |  | 2,864
Available-for-sale Securities, Gross Unrealized Gain | 82 |  | 82
Available-for-sale Securities, Gross Unrealized Loss | 0 |  | 0
Commercial mortgage-backed securities guaranteed by U.S. government agencies [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost | 2,933,046 |  | 2,986,297
Available for sale securities | 2,932,357 |  | 2,953,889
Available-for-sale Securities, Gross Unrealized Gain | 17,022 |  | 7,955
Available-for-sale Securities, Gross Unrealized Loss | $ (17,711) |  | $ (40,363)
Available-for-sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 169 |  | 197
Debt Securities, Available-for-sale, Unrealized Loss Position [Abstract] |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 432,254 |  | $ 179,258
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 1,590,803 |  | 1,969,504
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value | 2,023,057 |  | 2,148,762
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses [Abstract] |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 833 |  | 394
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 16,878 |  | 39,969
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | 17,711 |  | 40,363
Other debt securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost | 500 |  | 35,545
Available for sale securities | 472 |  | 35,430
Available-for-sale Securities, Gross Unrealized Gain | 0 |  | 12
Available-for-sale Securities, Gross Unrealized Loss | $ (28) |  | $ (127)
Available-for-sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 1 |  | 3
Debt Securities, Available-for-sale, Unrealized Loss Position [Abstract] |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 0 |  | $ 9,982
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 472 |  | 20,436
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value | 472 |  | 30,418
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses [Abstract] |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 |  | 63
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 28 |  | 64
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | 28 |  | 127
Residential Mortgage Backed Securities [Member] |  |  |
Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] |  |  |
Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Amortized Cost | 6,090,015 |  |
Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] |  |  |
Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Fair Value | $ 6,088,044 |  |
Available-for-sale Securities, Debt Maturities, Average Expected Life of Mortgage-backed Securities | 4 years 1 month 6 days |  |
Residential agency mortgage-backed securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost | $ 6,056,710 |  | 5,886,323
Available for sale securities | 6,040,086 |  | 5,804,708
Available-for-sale Securities, Gross Unrealized Gain | 35,131 |  | 16,149
Available-for-sale Securities, Gross Unrealized Loss | $ (51,755) |  | $ (97,764)
Available-for-sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract] |  |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 244 |  | 289
Debt Securities, Available-for-sale, Unrealized Loss Position [Abstract] |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 300,369 |  | $ 510,824
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 3,251,359 |  | 3,641,370
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value | 3,551,728 |  | 4,152,194
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses [Abstract] |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 1,016 |  | 1,158
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 50,739 |  | 96,606
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | 51,755 |  | 97,764
Residential non-agency mortgage-backed securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Available-for-sale Securities, Amortized Cost | 33,305 |  | 40,948
Available for sale securities | 47,958 |  | 59,736
Available-for-sale Securities, Gross Unrealized Gain | 14,653 |  | 18,788
Available-for-sale Securities, Gross Unrealized Loss | $ 0 |  | $ 0

X
- Definition The calculated weighted-average expected life of mortgage-backed securities based on prepayment assumptions as of the balance sheet date. + References No definition available. + Details
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