Stockholders' Equity - AOCI (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 2,542,848	$ 2,524,802	$ 3,383,952
OCI before reclassifications	(24,237)	(31,715)	367,840
Amounts reclassified from AOCI	0	0	(660,594)
Other Comprehensive (Loss)	(24,237)	(31,715)	(292,754)
Ending balance	1,988,849	2,542,848	2,524,802
Net Unrealized Gain/(Loss) on AFS Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	46,833	79,607	392,722
OCI before reclassifications	(25,492)	(32,774)	420,281
Amounts reclassified from AOCI	0	0	(733,396)
Other Comprehensive (Loss)	(25,492)	(32,774)	(313,115)
Ending balance	21,341	46,833	79,607
Net  Gain/(Loss) on Swaps
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	0	0	(22,675)
OCI before reclassifications	0	0	(50,127)
Amounts reclassified from AOCI	0	0	72,802
Other Comprehensive (Loss)	0	0	22,675
Ending balance	0	0	0
Net Unrealized Gain/(Loss) on Financing Agreements
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(1,255)	(2,314)	0
OCI before reclassifications	1,255	1,059	(2,314)
Amounts reclassified from AOCI	0	0	0
Other Comprehensive (Loss)	1,255	1,059	(2,314)
Ending balance	0	(1,255)	(2,314)
Accumulated Other Comprehensive Income
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	45,578	77,293	370,047
Ending balance	$ 21,341	$ 45,578	$ 77,293