Loans Receivable Aging Analysis (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Loan portfolio aging analysis
Accruing loans 30-59 days past due	$ 19,139	$ 25,761
Accruing loans 60-89 days past due	6,765	6,355
Accruing loans 90 days or more past due	214	604
Non-accrual loans	61,882	81,956
Total past due and non-accrual loans	88,000	114,676
Current loans receivable	4,400,095	3,948,162
Total loans receivable	4,488,095	4,062,838
Residential Real Estate
Loan portfolio aging analysis
Accruing loans 30-59 days past due	3,506	10,367
Accruing loans 60-89 days past due	1,686	1,055
Accruing loans 90 days or more past due	35	429
Non-accrual loans	6,798	10,702
Total past due and non-accrual loans	12,025	22,553
Current loans receivable	599,438	555,036
Total loans receivable	611,463	577,589
Commercial Real Estate
Loan portfolio aging analysis
Accruing loans 30-59 days past due	7,925	7,016
Accruing loans 60-89 days past due	3,592	2,709
Accruing loans 90 days or more past due	31	0
Non-accrual loans	39,717	51,438
Total past due and non-accrual loans	51,265	61,163
Current loans receivable	2,286,283	1,988,084
Total loans receivable	2,337,548	2,049,247
Other Commercial
Loan portfolio aging analysis
Accruing loans 30-59 days past due	5,310	3,673
Accruing loans 60-89 days past due	609	1,421
Accruing loans 90 days or more past due	74	160
Non-accrual loans	8,421	10,139
Total past due and non-accrual loans	14,414	15,393
Current loans receivable	911,486	836,643
Total loans receivable	925,900	852,036
Home Equity
Loan portfolio aging analysis
Accruing loans 30-59 days past due	1,374	2,432
Accruing loans 60-89 days past due	679	668
Accruing loans 90 days or more past due	17	5
Non-accrual loans	5,969	7,950
Total past due and non-accrual loans	8,039	11,055
Current loans receivable	386,631	355,410
Total loans receivable	394,670	366,465
Other Consumer
Loan portfolio aging analysis
Accruing loans 30-59 days past due	1,024	2,273
Accruing loans 60-89 days past due	199	502
Accruing loans 90 days or more past due	57	10
Non-accrual loans	977	1,727
Total past due and non-accrual loans	2,257	4,512
Current loans receivable	216,257	212,989
Total loans receivable	$ 218,514	$ 217,501

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

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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

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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

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-Section 45

-Paragraph 2

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

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