Variable Interest Entities - Summary (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Variable Interest Entity [Line Items]
AFS investment securities	$ 2,011,791	$ 2,601,013
Accrued expenses and other liabilities	227,351	206,023
Other assets	275,113	253,871
Assets	20,747,883	21,688,017
Liabilities	17,898,749	18,889,628
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Maximum Loss	155,841	168,216
Assets	127,371	132,743
Liabilities	22,766	15,762
Variable Interest Entity, Not Primary Beneficiary | Multifamily Loan Securitization, Asset
Variable Interest Entity [Line Items]
Maximum Loss	51,301	56,784
AFS investment securities	51,301	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	53,639	60,531
Other assets	76,070	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	$ 22,432	$ 15,428