Loans and Leases (Details 6)		12 Months Ended
		Dec. 31, 2017 USD ($) contract Contract		Dec. 31, 2016 USD ($) contract Contract		Dec. 31, 2015 USD ($) contract Contract
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts		50	[1]	54	[2]	97	[3]
Financing Receivable, Modifications, Pre-Modification Recorded Investment		$ 69,737,000	[1]	$ 100,161,000	[2]	$ 175,728,000	[3]
Financing Receivable, Modifications, Post-Modification Recorded Investment		$ 59,237,000	[1]	$ 89,443,000	[2]	$ 174,858,000	[3]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts		1	[1]	4	[2]	3	[3]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	[4]	$ 1,000	[1]	$ 6,502,000		$ 2,825,000	[3]
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down		$ 68,000		$ 0		$ 96,900
Mortgages [Member] | Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts		5		12		21
Financing Receivable, Modifications, Pre-Modification Recorded Investment		$ 2,527,000		$ 13,833,000		$ 43,536,000
Financing Receivable, Modifications, Post-Modification Recorded Investment		$ 2,463,000		$ 6,099,000		$ 43,012,000
Financing Receivable, Modifications, Subsequent Default, Number of Contracts		0		0		2
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	[4]	$ 0		$ 0		$ 2,670,000
Mortgages [Member] | Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts		8		10		18
Financing Receivable, Modifications, Pre-Modification Recorded Investment		$ 1,328,000		$ 7,091,000		$ 3,128,000
Financing Receivable, Modifications, Post-Modification Recorded Investment		$ 489,000		$ 6,439,000		$ 2,961,000
Financing Receivable, Modifications, Subsequent Default, Number of Contracts		0		2		1
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	[4]	$ 0		$ 5,000,000		$ 155,000
Real Estate Construction [Member] | Commercial Real Estate Construction Loan Receivable [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts		1				8
Financing Receivable, Modifications, Pre-Modification Recorded Investment		$ 362,000				$ 23,881,000
Financing Receivable, Modifications, Post-Modification Recorded Investment		$ 0				$ 23,881,000
Financing Receivable, Modifications, Subsequent Default, Number of Contracts		0		0		0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	[4]	$ 0		$ 0		$ 0
Commercial Portfolio Segment [Member] | Cash Flow [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts | contract		14		14		25
Financing Receivable, Modifications, Pre-Modification Recorded Investment		$ 27,703,000		$ 30,788,000		$ 2,718,000
Financing Receivable, Modifications, Post-Modification Recorded Investment		$ 18,468,000		$ 30,788,000		$ 2,539,000
Commercial Portfolio Segment [Member] | Asset Based [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts | contract		10		5		13
Financing Receivable, Modifications, Pre-Modification Recorded Investment		$ 7,987,000		$ 2,158,000		$ 8,400,000
Financing Receivable, Modifications, Post-Modification Recorded Investment		$ 7,987,000		$ 2,158,000		$ 8,400,000
Financing Receivable, Modifications, Subsequent Default, Number of Contracts | Contract		0		2		0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	[4]	$ 0		$ 1,502,000		$ 0
Commercial Portfolio Segment [Member] | Venture Capital Loans [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts | contract		11
Financing Receivable, Modifications, Pre-Modification Recorded Investment		$ 29,733,000
Financing Receivable, Modifications, Post-Modification Recorded Investment		$ 29,733,000
Commercial Portfolio Segment [Member] | Equipment Finance Commercial Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts				7		10
Financing Receivable, Modifications, Pre-Modification Recorded Investment				$ 44,196,000		$ 93,868,000
Financing Receivable, Modifications, Post-Modification Recorded Investment				$ 42,572,000		$ 93,868,000
Financing Receivable, Modifications, Subsequent Default, Number of Contracts				0		0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	[4]			$ 0		$ 0
Consumer Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts		1		5		2
Financing Receivable, Modifications, Pre-Modification Recorded Investment		$ 97,000		$ 850,000		$ 197,000
Financing Receivable, Modifications, Post-Modification Recorded Investment		$ 97,000		$ 142,000		$ 197,000
Equipment Finance Commercial Financing Receivable [Member] | Cash Flow [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts | Contract		1
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	[4]	$ 1,000
Equipment Finance Commercial Financing Receivable [Member] | Venture Capital Loans [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts | Contract		0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	[4]	$ 0
Commercial Portfolio Segment [Member] | Commercial Portfolio Segment [Member] | Cash Flow [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts | Contract				0		0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	[4]			$ 0		$ 0
Commercial Real Estate Construction Loan Receivable [Member] | Real Estate Construction [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts				1
Financing Receivable, Modifications, Pre-Modification Recorded Investment				$ 1,245,000
Financing Receivable, Modifications, Post-Modification Recorded Investment				$ 1,245,000
Consumer Portfolio Segment [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts | Contract		0		0		0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	[4]	$ 0		$ 0		$ 0

[1] Represents the balance at December 31, 2017, and is net of charge-offs of $68,000

[2] Represents the balance at December 31, 2016, and there were

[3] Represents the balance at December 31, 2015, and is net of charge-offs of $96,900.

[4] The population of defaulted restructured loans for the period indicated includes only those loans restructured during the preceding 12-month period. For example, for the year ended December 31, 2017, the population of defaulted restructured loans includes only those loans restructured after December 31, 2016. The table excludes defaulted troubled restructurings in those classes for which the recorded investment was zero at the end of the period.