Financing Agreements - Borrowings Under Repurchase Agreement (Details) - Repurchase Agreement Borrowings - Fair Value - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	$ 3,371,921	$ 3,227,558
Weighted Average Interest Rate	7.15%	6.58%
Within 30 days
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	$ 3,135,319	$ 3,060,111
Weighted Average Interest Rate	7.20%	6.60%
Over 30 days to 3 months
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	$ 236,602	$ 167,447
Weighted Average Interest Rate	6.51%	6.19%
Over 3 months to 12 months
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	$ 0	$ 0
Weighted Average Interest Rate	0.00%	0.00%
Over 12 months
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	$ 0	$ 0
Weighted Average Interest Rate	0.00%	0.00%