Loans Receivable and Credit Quality Loans Text Disclosures (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Related Parties	$ 0	$ 0	$ 9,500,000
Loans and Leases Receivable, Deferred Income	(4,100,000)	(4,200,000)
Servicing Asset	114,100,000	138,900,000
Transfer of Portfolio Loans and Leases to Held-for-sale	5,593,000	385,423,000	(526,000)
Gain on sale of loans, net	2,519,000	3,225,000	2,489,000
Financing Receivable, Modifications, Recorded Investment	54,500,000	54,500,000
Loans and Leases Receivable, Impaired, Commitment to Lend	100,000	100,000
Loans and Leases Receivable, Net of Deferred Income	5,112,459,000	4,814,136,000
Residential Loans Transferred to Held for Sale in Q3 2012 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transfer of Portfolio Loans and Leases to Held-for-sale		108,700,000
Gain on sale of loans, net		900,000
Transferred to Held For Sale Pacific Northwest Transaction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transfer of Portfolio Loans and Leases to Held-for-sale		276,700,000
Holding Company and Non-Banks [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income	100,000	500,000
Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income	866,053,000	806,326,000
Commercial Loan [Member] | Transferred to Held For Sale Pacific Northwest Transaction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transfer of Portfolio Loans and Leases to Held-for-sale		40,800,000
Commercial Real Estate Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income	1,813,394,000	1,691,350,000
Commercial Real Estate Portfolio Segment [Member] | Transferred to Held For Sale Pacific Northwest Transaction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transfer of Portfolio Loans and Leases to Held-for-sale		151,200,000
Construction Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income	153,917,000	137,570,000
Construction Loans [Member] | Transferred to Held For Sale Pacific Northwest Transaction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transfer of Portfolio Loans and Leases to Held-for-sale		2,900,000
Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income	2,032,294,000	1,906,089,000
Residential Portfolio Segment [Member] | Transferred to Held For Sale Pacific Northwest Transaction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transfer of Portfolio Loans and Leases to Held-for-sale		78,500,000
Home Equity Line of Credit [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income	113,660,000	123,551,000
Home Equity Line of Credit [Member] | Transferred to Held For Sale Pacific Northwest Transaction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transfer of Portfolio Loans and Leases to Held-for-sale		2,000,000
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Net of Deferred Income	133,141,000	149,250,000
Consumer Portfolio Segment [Member] | Transferred to Held For Sale Pacific Northwest Transaction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transfer of Portfolio Loans and Leases to Held-for-sale		1,300,000
Performing Financing Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Modifications, Recorded Investment	$ 28,400,000	$ 26,700,000