Securities (Schedule of Available-for-sale Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 10,087,179	$ 5,470,523
Gross Unrealized Gains	51,025	96,596
Gross Unrealized Losses	(172,851)	(22,461)
Fair Value	9,965,353	5,544,658
Debt securities available for sale
Debt Securities, Available-for-sale [Line Items]
Accrued interest receivables	33,100	22,300
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,049,238	50,310
Gross Unrealized Gains	130	451
Gross Unrealized Losses	(16,687)	0
Fair Value	1,032,681	50,761
U.S. government agency and U.S. government-sponsored enterprise debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,333,984	806,814
Gross Unrealized Gains	2,697	8,765
Gross Unrealized Losses	(34,710)	(1,260)
Fair Value	1,301,971	814,319
US government agencies And U.S. government-sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,242,043	1,125,174
Gross Unrealized Gains	15,791	34,306
Gross Unrealized Losses	(28,854)	(5,710)
Fair Value	1,228,980	1,153,770
US government agencies And U.S. government-sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,968,789	1,634,553
Gross Unrealized Gains	8,629	27,952
Gross Unrealized Losses	(49,135)	(1,611)
Fair Value	2,928,283	1,660,894
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	519,381	382,573
Gross Unrealized Gains	10,065	13,588
Gross Unrealized Losses	(6,288)	(88)
Fair Value	523,158	396,073
Non-agency commercial mortgage-backed Securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	498,920	234,965
Gross Unrealized Gains	3,000	6,107
Gross Unrealized Losses	(5,477)	(1,230)
Fair Value	496,443	239,842
Non-agency residential mortgage-backed Securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	889,937	288,520
Gross Unrealized Gains	971	1,761
Gross Unrealized Losses	(8,977)	(506)
Fair Value	881,931	289,775
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	657,516	406,323
Gross Unrealized Gains	8,738	3,493
Gross Unrealized Losses	(16,589)	(3,848)
Fair Value	649,665	405,968
Foreign government bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	260,447	183,828
Gross Unrealized Gains	767	163
Gross Unrealized Losses	(3,481)	(1,460)
Fair Value	257,733	182,531
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	74,674	63,463
Gross Unrealized Gains	185	10
Gross Unrealized Losses	(301)	(242)
Fair Value	74,558	63,231
CLOs
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	592,250	294,000
Gross Unrealized Gains	52	0
Gross Unrealized Losses	(2,352)	(6,506)
Fair Value	$ 589,950	$ 287,494

Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

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