Borrowings - Stated Maturity and Maturity to Call Date (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Debt Instrument [Line Items]
Stated maturity, 2022	$ 3,636,488
Stated maturity, 2023	2,731,907
Stated maturity, 2024	1,924,122
Stated maturity, 2025	1,418,489
Stated maturity, 2026	2,151,693
Stated maturity, 2027 and after	1,797,903
Maturity to call date, 2022	3,636,488
Maturity to Call Date, 2023	2,731,907
Maturity to Call Date, 2024	1,924,122
Maturity to Call Date, 2025	1,418,489
Maturity to Call Date, 2026	2,151,693
Maturity to Call Date, 2027 and after	1,797,903
Total principal amount, maturity to call date	13,660,602
Hedge accounting adjustments	33,426
Total principal amount, after adjustments	13,694,028
Brokered Deposits
Debt Instrument [Line Items]
Stated maturity, 2022	2,918,335
Stated maturity, 2023	2,033,829
Stated maturity, 2024	1,236,522
Stated maturity, 2025	270,174
Stated maturity, 2026	1,033,313
Stated maturity, 2027 and after	47,401
Maturity to call date, 2022	2,918,335
Maturity to Call Date, 2023	2,033,829
Maturity to Call Date, 2024	1,236,522
Maturity to Call Date, 2025	270,174
Maturity to Call Date, 2026	1,033,313
Maturity to Call Date, 2027 and after	47,401
Total principal amount, maturity to call date	7,539,574
Hedge accounting adjustments	33,426
Total principal amount, after adjustments	7,573,000
Unsecured Debt
Debt Instrument [Line Items]
Stated maturity, 2022	0
Stated maturity, 2023	0
Stated maturity, 2024	0
Stated maturity, 2025	500,000
Stated maturity, 2026	500,000
Stated maturity, 2027 and after	0
Maturity to call date, 2022	0
Maturity to Call Date, 2023	0
Maturity to Call Date, 2024	0
Maturity to Call Date, 2025	500,000
Maturity to Call Date, 2026	500,000
Maturity to Call Date, 2027 and after	0
Total principal amount, maturity to call date	1,000,000
Hedge accounting adjustments	0
Total principal amount, after adjustments	1,000,000
Secured Borrowings
Debt Instrument [Line Items]
Stated maturity, 2022	718,153
Stated maturity, 2023	698,078
Stated maturity, 2024	687,600
Stated maturity, 2025	648,315
Stated maturity, 2026	618,380
Stated maturity, 2027 and after	1,750,502
Maturity to call date, 2022	718,153
Maturity to Call Date, 2023	698,078
Maturity to Call Date, 2024	687,600
Maturity to Call Date, 2025	648,315
Maturity to Call Date, 2026	618,380
Maturity to Call Date, 2027 and after	1,750,502
Total principal amount, maturity to call date	5,121,028
Hedge accounting adjustments	0
Total principal amount, after adjustments	$ 5,121,028

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