Loans Receivable and Allowance for Credit Losses (Amortized Cost of Loans on Nonaccrual Status) (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Financing Receivable, Nonaccrual [Line Items]
Total nonaccrual loans with no related allowance for loan losses	$ 126,676
Commercial Lending
Financing Receivable, Nonaccrual [Line Items]
Total nonaccrual loans with no related allowance for loan losses	110,096
Commercial Lending | C&I
Financing Receivable, Nonaccrual [Line Items]
Total nonaccrual loans with no related allowance for loan losses	62,040
Commercial Lending | CRE
Financing Receivable, Nonaccrual [Line Items]
Total nonaccrual loans with no related allowance for loan losses	45,537
Commercial Lending | Total CRE
Financing Receivable, Nonaccrual [Line Items]
Total nonaccrual loans with no related allowance for loan losses	48,056
Commercial Lending | Real estate loan | Multifamily
Financing Receivable, Nonaccrual [Line Items]
Total nonaccrual loans with no related allowance for loan losses	2,519
Consumer Lending
Financing Receivable, Nonaccrual [Line Items]
Total nonaccrual loans with no related allowance for loan losses	16,580
Consumer Lending | Real estate loan | Single-family
Financing Receivable, Nonaccrual [Line Items]
Total nonaccrual loans with no related allowance for loan losses	6,013
Consumer Lending | HELOCs
Financing Receivable, Nonaccrual [Line Items]
Total nonaccrual loans with no related allowance for loan losses	8,076
Consumer Lending | Total residential mortgage
Financing Receivable, Nonaccrual [Line Items]
Total nonaccrual loans with no related allowance for loan losses	14,089
Consumer Lending | Other consumer
Financing Receivable, Nonaccrual [Line Items]
Total nonaccrual loans with no related allowance for loan losses	$ 2,491