Loans, Allowance for Loan Losses and Allowance for Unfunded Credit Commitments - Recorded Investment in Loans Modified in TDRs within Previous 12 months Subsequently Defaulted (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs modified within the previous 12 months that defaulted in the period	$ 1,485	$ 47,933	$ 0
Global fund banking
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs modified within the previous 12 months that defaulted in the period	0	0	0
Investor dependent
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs modified within the previous 12 months that defaulted in the period	0	10,639	0
Investor dependent | Early stage
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs modified within the previous 12 months that defaulted in the period	0	0	0
Investor dependent | Mid stage
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs modified within the previous 12 months that defaulted in the period	0	0	0
Investor dependent | Later stage
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs modified within the previous 12 months that defaulted in the period	0	10,639	0
Cash flow dependent
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs modified within the previous 12 months that defaulted in the period	487	37,294	0
Cash flow dependent | Sponsor led buyout
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs modified within the previous 12 months that defaulted in the period	0	37,294
Cash flow dependent | Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs modified within the previous 12 months that defaulted in the period	487	0	0
Private Bank
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs modified within the previous 12 months that defaulted in the period	0	0	0
Balance sheet dependent
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs modified within the previous 12 months that defaulted in the period	0	0	0
Premium wine
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs modified within the previous 12 months that defaulted in the period	998	0	0
Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs modified within the previous 12 months that defaulted in the period	0	0	0
SBA loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs modified within the previous 12 months that defaulted in the period	$ 0	$ 0	$ 0