Loans and Leases (Details Textual)	3 Months Ended
	Mar. 31, 2020 USD ($) contract	Mar. 31, 2019 USD ($) contract	Dec. 31, 2019 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivable, 90 or more days past due	$ 12,036,000		$ 11,085,000
Receivable, 30-89 days past due	14,821,000		9,788,000
Nonaccrual loans and leases	95,602,000		92,353,000
Allowance for Loan and Lease Losses, Period Increase (Decrease)	83,000,000
Provision	98,000,000	$ 4,000,000
Credit Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans and leases	$ 42,900,000
Percentage of nonaccrual loans and leases	45.00%
Nonaccrual
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivable, 90 or more days past due	$ 12,000,000.0		11,100,000
Receivable, 30-89 days past due	6,600,000		1,200,000
Financing receivable, nonaccrual status, current	$ 77,000,000.0		80,000,000.0
Venture Capital Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans | contract	1
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	$ 2,300,000
Other Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans | contract	1	2
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	$ 9,000	$ 64,000
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivable, 90 or more days past due	5,011,000		4,164,000
Receivable, 30-89 days past due	8,156,000		2,800,000
Nonaccrual loans and leases	73,442,000		70,672,000
Provision	37,459,000	$ 5,033,000
Commercial | Venture Capital Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivable, 90 or more days past due	2,989,000		0
Receivable, 30-89 days past due	3,272,000		0
Nonaccrual loans and leases	18,612,000		12,916,000
Commercial | Other Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivable, 90 or more days past due	2,022,000		4,164,000
Receivable, 30-89 days past due	4,884,000		2,781,000
Nonaccrual loans and leases	$ 37,726,000		$ 27,594,000