Loans Receivable and Allowance for Loan Losses (Impaired Loans) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Financing receivable, impaired
Unpaid Principal Balance	$ 285,168	$ 289,737
Recorded Investment	246,803	248,436
Related Allowance	(20,723)	(19,732)
Net Investment	226,080	228,704
Consumer and other loans \| Home equity and other consumer
Financing receivable, impaired
Unpaid Principal Balance, Loans with an allowance recorded	6,813	5,436
Recorded Investment, Loans with an allowance recorded	6,504	5,153
Related Allowance	(4,938)	(3,810)
Net Investment, Loans with an allowance recorded	1,566	1,343
Mortgage loans \| Residential \| Full documentation interest-only
Financing receivable, impaired
Unpaid Principal Balance, Loans with an allowance recorded	51,533	55,352
Recorded Investment, Loans with an allowance recorded	43,187	46,331
Related Allowance	(3,503)	(3,391)
Net Investment, Loans with an allowance recorded	39,684	42,940
Mortgage loans \| Residential \| Full documentation amortizing loans
Financing receivable, impaired
Unpaid Principal Balance, Loans with an allowance recorded	52,320	43,044
Recorded Investment, Loans with an allowance recorded	47,983	39,994
Related Allowance	(1,841)	(1,425)
Net Investment, Loans with an allowance recorded	46,142	38,569
Mortgage loans \| Residential \| Reduced documentation interest-only
Financing receivable, impaired
Unpaid Principal Balance, Loans with an allowance recorded	89,147	90,171
Recorded Investment, Loans with an allowance recorded	75,831	76,960
Related Allowance	(4,538)	(4,661)
Net Investment, Loans with an allowance recorded	71,293	72,299
Mortgage loans \| Residential \| Reduced documentation amortizing
Financing receivable, impaired
Unpaid Principal Balance, Loans with an allowance recorded	21,302	19,463
Recorded Investment, Loans with an allowance recorded	19,778	18,117
Related Allowance	(637)	(827)
Net Investment, Loans with an allowance recorded	19,141	17,290
Mortgage loans \| Multi-family
Financing receivable, impaired
Unpaid Principal Balance, Loans with an allowance recorded	24,380	34,972
Unpaid Principal Balance, Loans without an allowance recorded	14,290	16,308
Recorded Investment, Loans with an allowance recorded	20,974	28,109
Recorded Investment, Loans without an allowance recorded	13,016	14,502
Related Allowance	(2,785)	(3,172)
Net Investment, Loans with an allowance recorded	18,189	24,937
Net Investment, Loans without an allowance recorded	13,016	14,502
Mortgage loans \| Commercial real estate
Financing receivable, impaired
Unpaid Principal Balance, Loans with an allowance recorded	25,383	24,991
Recorded Investment, Loans with an allowance recorded	19,530	19,270
Related Allowance	(2,481)	(2,446)
Net Investment, Loans with an allowance recorded	$ 17,049	$ 16,824

Represents the net amount of investment of impaired financing receivables.

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.

+ References

No definition available.

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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=35738203&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

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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

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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

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-Section 50

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-URI http://asc.fasb.org/extlink&oid=35738203&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=35738203&loc=d3e5212-111524

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