Shareholders' Equity - Schedule of AOCI (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Rollforward]
Balance	$ 2,597,431	$ 2,755,422	$ 3,129,389
Current year other comprehensive loss	91	(68)	39,775
Balance	2,505,878	2,597,431	2,755,422
Unrealized Gain (Loss) on Investment Securities, net
Accumulated Other Comprehensive Income (Loss) [Rollforward]
Balance	0	78,715
Amounts reclassified from cumulative other comprehensive income to retained earnings	0	(78,715)
Current year other comprehensive loss	0	0
Balance	0	0	78,715
Equity in Unrealized Gain (Loss) of Investees
Accumulated Other Comprehensive Income (Loss) [Rollforward]
Balance	(266)	643
Amounts reclassified from cumulative other comprehensive income to retained earnings	175	(841)
Current year other comprehensive loss	91	(68)
Balance	0	(266)	643
Cumulative Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Rollforward]
Balance	(266)	79,358	39,583
Amounts reclassified from cumulative other comprehensive income to retained earnings	175	(79,556)
Current year other comprehensive loss		(68)
Balance	$ 0	$ (266)	$ 79,358

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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