Fair Value - Financial Instruments Not Carried at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Financial assets not carried at fair value:
HTM debt securities	$ 747,484	$ 691,746
Financial liabilities not carried at fair value:
Unsecured senior notes	2,326,988	1,828,590
Carrying Value
Financial assets not carried at fair value:
Loans	18,050,646	15,477,624
HTM debt securities	743,556	683,136
Financial liabilities not carried at fair value:
Secured financing agreements, CLOs and SASB	17,186,898	15,192,966
Unsecured senior notes	2,326,988	1,828,590
Fair Value
Financial assets not carried at fair value:
Loans	17,843,579	15,526,235
HTM debt securities	704,285	656,864
Financial liabilities not carried at fair value:
Secured financing agreements, CLOs and SASB	16,953,413	15,266,440
Unsecured senior notes	$ 2,119,427	$ 1,893,065