Loans Receivable Aging Analysis (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Loan portfolio aging analysis
Accruing loans 30-59 days past due	$ 26,255	$ 19,139
Accruing loans 60-89 days past due	7,195	6,765
Accruing loans 90 days or more past due	2,357	214
Non-accrual loans	60,287	61,882
Total past due and non-accrual loans	96,094	88,000
Current loans receivable	4,591,575	4,400,095
Total loans receivable	4,687,669	4,488,095
Residential Real Estate
Loan portfolio aging analysis
Accruing loans 30-59 days past due	4,585	3,506
Accruing loans 60-89 days past due	1,022	1,686
Accruing loans 90 days or more past due	222	35
Non-accrual loans	7,365	6,798
Total past due and non-accrual loans	13,194	12,025
Current loans receivable	624,271	599,438
Total loans receivable	637,465	611,463
Commercial Real Estate
Loan portfolio aging analysis
Accruing loans 30-59 days past due	9,663	7,925
Accruing loans 60-89 days past due	4,204	3,592
Accruing loans 90 days or more past due	47	31
Non-accrual loans	35,067	39,717
Total past due and non-accrual loans	48,981	51,265
Current loans receivable	2,369,862	2,286,283
Total loans receivable	2,418,843	2,337,548
Other Commercial
Loan portfolio aging analysis
Accruing loans 30-59 days past due	7,621	5,310
Accruing loans 60-89 days past due	1,038	609
Accruing loans 90 days or more past due	2,056	74
Non-accrual loans	11,541	8,421
Total past due and non-accrual loans	22,256	14,414
Current loans receivable	984,917	911,486
Total loans receivable	1,007,173	925,900
Home Equity
Loan portfolio aging analysis
Accruing loans 30-59 days past due	2,997	1,374
Accruing loans 60-89 days past due	734	679
Accruing loans 90 days or more past due	0	17
Non-accrual loans	5,587	5,969
Total past due and non-accrual loans	9,318	8,039
Current loans receivable	393,652	386,631
Total loans receivable	402,970	394,670
Other Consumer
Loan portfolio aging analysis
Accruing loans 30-59 days past due	1,389	1,024
Accruing loans 60-89 days past due	197	199
Accruing loans 90 days or more past due	32	57
Non-accrual loans	727	977
Total past due and non-accrual loans	2,345	2,257
Current loans receivable	218,873	216,257
Total loans receivable	$ 221,218	$ 218,514

Financing receivable recorded investment past due and non accrual loans.

No definition available.

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- Definition

Financing receivables that are less than 60 days past due but more than 29 days past due.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953401-111524

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- Definition

Financing receivables that are less than 90 days past due but more than 59 days past due.

+ References

+ Details

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- Definition

Financing receivables that are current.

+ References

+ Details

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- Definition

Financing receivables that are equal to or greater than 90 days past due.

+ References

+ Details

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5111-111524

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5074-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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