Variable Interest Entities - Summary (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Variable Interest Entity [Line Items]
Investment securities available-for-sale	$ 2,661,079	$ 4,273,864
Accrued expenses and other liabilities	206,386	203,962
Other assets	257,041	260,204
Assets	21,619,201	21,094,429
Liabilities	18,883,805	18,208,118
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Maximum Loss	169,118	200,769
Assets	133,726	167,097
Liabilities	15,847	17,567
Variable Interest Entity, Not Primary Beneficiary | Multifamily Loan Securitization, Asset
Variable Interest Entity [Line Items]
Maximum Loss	57,525	81,103
Investment securities available-for-sale	57,525	81,103
Variable Interest Entity, Not Primary Beneficiary | Multifamily Loan Securitization, Liability
Variable Interest Entity [Line Items]
Maximum Loss	50,901	50,901
Accrued expenses and other liabilities	338	338
Variable Interest Entity, Not Primary Beneficiary | Affordable Housing Partnership, Asset
Variable Interest Entity [Line Items]
Maximum Loss	60,692	68,765
Other assets	76,201	85,994
Variable Interest Entity, Not Primary Beneficiary | Affordable Housing Partnership, Liability
Variable Interest Entity [Line Items]
Maximum Loss	0	0
Accrued expenses and other liabilities	$ 15,509	$ 17,229