Financings - Repurchase Agreements Remaining Maturities (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Borrowings Under Repurchase Agreements
Securitized debt	$ 1,057,000
Certain characteristics of the Company's repurchase agreements
Repurchase agreements	2,824,801,000	$ 2,818,837,000
Repurchase agreement, net amounts of assets presented in consolidated balance sheets	2,824,877,000	2,818,837,000
1 to 29 days
Certain characteristics of the Company's repurchase agreements
Repurchase agreements	1,480,286,000	1,867,957,000
30 to 59 days
Certain characteristics of the Company's repurchase agreements
Repurchase agreements	552,786,000	144,778,000
60 to 89 days
Certain characteristics of the Company's repurchase agreements
Repurchase agreements	255,814,000	555,695,000
Greater than or equal to 90 days
Certain characteristics of the Company's repurchase agreements
Repurchase agreements	535,991,000	$ 250,407,000
Commercial Facility
Borrowings Under Repurchase Agreements
Line of credit facility, maximum borrowing capacity	$ 200.0

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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