Variable Interest Entities - Summary (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Variable Interest Entity [Line Items]
AFS investment securities	$ 2,112,852	$ 2,601,013
Accrued expenses and other liabilities	191,229	206,023
Other assets	257,082	253,871
Assets	21,361,564	21,688,017
Liabilities	18,530,403	18,889,628
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Maximum Loss	158,967	168,216
Assets	123,280	132,743
Liabilities	15,548	15,762
Variable Interest Entity, Not Primary Beneficiary | Multifamily Loan Securitization, Asset
Variable Interest Entity [Line Items]
Maximum Loss	53,716	56,784
AFS investment securities	53,716	56,784
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	334	334
Variable Interest Entity, Not Primary Beneficiary | Affordable Housing Partnership, Asset
Variable Interest Entity [Line Items]
Maximum Loss	54,350	60,531
Other assets	69,564	75,959
Variable Interest Entity, Not Primary Beneficiary | Affordable Housing Partnership, Liability
Variable Interest Entity [Line Items]
Maximum Loss	0	0
Accrued expenses and other liabilities	$ 15,214	$ 15,428