Loans Receivable and Allowance for Loan Losses (Impaired Loans) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
With an allowance recorded:
Related Allowance	$ (13,976)	$ (14,813)
Total impaired loans
Unpaid Principal Balance	262,391	271,492
Recorded Investment	229,803	237,518
Related Allowance	(13,976)	(14,813)
Net Investment	215,827	222,705
Home Equity Lines of Credit \| Home Equity and Other Consumer
With an allowance recorded:
Unpaid Principal Balance	4,896	5,595
Recorded Investment	4,537	4,968
Related Allowance	(381)	(421)
Net Investment	4,156	4,547
Total impaired loans
Related Allowance	(381)	(421)
Mortgage Loans \| Residential \| Full documentation interest-only
With an allowance recorded:
Unpaid Principal Balance	34,525	37,454
Recorded Investment	28,292	30,631
Related Allowance	(3,724)	(4,051)
Net Investment	24,568	26,580
Total impaired loans
Related Allowance	(3,724)	(4,051)
Mortgage Loans \| Residential \| Full documentation amortizing
With an allowance recorded:
Unpaid Principal Balance	73,169	69,242
Recorded Investment	66,492	63,223
Related Allowance	(3,021)	(2,534)
Net Investment	63,471	60,689
Total impaired loans
Related Allowance	(3,021)	(2,534)
Mortgage Loans \| Residential \| Reduced documentation interest-only
With an allowance recorded:
Unpaid Principal Balance	47,328	55,939
Recorded Investment	39,696	46,540
Related Allowance	(3,720)	(4,253)
Net Investment	35,976	42,287
Total impaired loans
Related Allowance	(3,720)	(4,253)
Mortgage Loans \| Residential \| Reduced documentation amortizing
With an allowance recorded:
Unpaid Principal Balance	69,004	57,955
Recorded Investment	61,885	52,520
Related Allowance	(2,872)	(2,310)
Net Investment	59,013	50,210
Total impaired loans
Related Allowance	(2,872)	(2,310)
Mortgage Loans \| Multi-Family
With an allowance recorded:
Unpaid Principal Balance	5,791	8,029
Recorded Investment	5,676	7,950
Related Allowance	(173)	(456)
Net Investment	5,503	7,494
Without an allowance recorded:
Unpaid Principal Balance	11,761	19,523
Recorded Investment	10,057	16,693
Net Investment	10,057	16,693
Total impaired loans
Related Allowance	(173)	(456)
Mortgage Loans \| Commercial Real Estate
With an allowance recorded:
Unpaid Principal Balance	942	6,651
Recorded Investment	1,027	6,723
Related Allowance	(85)	(788)
Net Investment	942	5,935
Without an allowance recorded:
Unpaid Principal Balance	14,975	11,104
Recorded Investment	12,141	8,270
Net Investment	12,141	8,270
Total impaired loans
Related Allowance	$ (85)	$ (788)

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No definition available.

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- Definition

Represents the net amount of investment of impaired financing receivables for which there is no related allowance for credit losses.

+ References

No definition available.

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- Definition

Represents the net amount of investment of impaired financing receivables for which there is a related allowance for credit losses.

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- Definition

Impaired Financing Receivable, Total [Abstract]

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- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953550-111524

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5212-111524

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- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5212-111524

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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- Definition

Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5212-111524

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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- Definition

Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5212-111524

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