Securities (Continuous Unrealized Losses) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	$ 100,546	$ 163,128
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(510)	(1,518)
Available-for-sale debt securities, 12 Months or More, Fair Value	1,074,195	2,087,534
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(13,311)	(69,249)
Available-for-sale debt securities Fair Value, Total	1,174,741	2,250,662
Available-for-sale debt securities, Gross Unrealized Loss, Total	(13,821)	(70,767)
U.S. Treasury securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	0	0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	0	0
Available-for-sale debt securities, 12 Months or More, Fair Value	326,535	516,520
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(2,674)	(12,899)
Available-for-sale debt securities Fair Value, Total	326,535	516,520
Available-for-sale debt securities, Gross Unrealized Loss, Total	(2,674)	(12,899)
U.S. government agency and U.S. government sponsored enterprise debt securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	22,442	22,755
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(17)	(238)
Available-for-sale debt securities, 12 Months or More, Fair Value	0	159,814
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	0	(2,456)
Available-for-sale debt securities Fair Value, Total	22,442	182,569
Available-for-sale debt securities, Gross Unrealized Loss, Total	(17)	(2,694)
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	10,210	26,886
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(81)	(245)
Available-for-sale debt securities, 12 Months or More, Fair Value	208,330	274,666
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(4,232)	(12,449)
Available-for-sale debt securities Fair Value, Total	218,540	301,552
Available-for-sale debt securities, Gross Unrealized Loss, Total	(4,313)	(12,694)
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	11,679	75,675
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(123)	(491)
Available-for-sale debt securities, 12 Months or More, Fair Value	145,595	653,660
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(1,282)	(14,061)
Available-for-sale debt securities Fair Value, Total	157,274	729,335
Available-for-sale debt securities, Gross Unrealized Loss, Total	(1,405)	(14,552)
Municipal securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	4,890	9,458
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(10)	(104)
Available-for-sale debt securities, 12 Months or More, Fair Value	9,950	30,295
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(28)	(928)
Available-for-sale debt securities Fair Value, Total	14,840	39,753
Available-for-sale debt securities, Gross Unrealized Loss, Total	(38)	(1,032)
Non-agency commercial mortgage-backed securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	7,916
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(4)
Available-for-sale debt securities, 12 Months or More, Fair Value	0
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	0
Available-for-sale debt securities Fair Value, Total	7,916
Available-for-sale debt securities, Gross Unrealized Loss, Total	(4)
Non-agency residential mortgage-backed securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	0	3,067
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	0	(19)
Available-for-sale debt securities, 12 Months or More, Fair Value	3,917	3,949
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(14)	(166)
Available-for-sale debt securities Fair Value, Total	3,917	7,016
Available-for-sale debt securities, Gross Unrealized Loss, Total	(14)	(185)
Corporate debt securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	1,244	10,869
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(6)	(381)
Available-for-sale debt securities, 12 Months or More, Fair Value	9,912	0
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(88)	0
Available-for-sale debt securities Fair Value, Total	11,156	10,869
Available-for-sale debt securities, Gross Unrealized Loss, Total	(94)	(381)
Foreign bonds
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	14,349	14,418
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(94)	(40)
Available-for-sale debt securities, 12 Months or More, Fair Value	369,956	448,630
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(4,993)	(26,290)
Available-for-sale debt securities Fair Value, Total	384,305	463,048
Available-for-sale debt securities, Gross Unrealized Loss, Total	(5,087)	$ (26,330)
Asset-backed securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	27,816
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(175)
Available-for-sale debt securities, 12 Months or More, Fair Value	0
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	0
Available-for-sale debt securities Fair Value, Total	27,816
Available-for-sale debt securities, Gross Unrealized Loss, Total	$ (175)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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