Loans Receivable and Allowance for Loan Losses - Impaired Loans by Segment and Class (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
With an allowance recorded:
Related Allowance	$ (9,048)	$ (9,378)
Total impaired loans
Unpaid Principal Balance	242,330	244,574
Recorded Investment	212,371	213,663
Related Allowance	(9,048)	(9,378)
Net Investment	203,323	204,285
Consumer and other loans \| Home equity lines of credit
With an allowance recorded:
Unpaid Principal Balance	4,261	4,414
Recorded Investment	3,896	4,049
Related Allowance	(286)	(310)
Net Investment	3,610	3,739
Total impaired loans
Related Allowance	(286)	(310)
Commercial and industrial
Without an allowance recorded:
Unpaid Principal Balance	80	90
Recorded Investment	32	42
Net Investment	32	42
Mortgage loans \| Residential \| Full documentation interest-only
With an allowance recorded:
Unpaid Principal Balance	17,600	21,202
Recorded Investment	13,753	16,535
Related Allowance	(1,634)	(1,863)
Net Investment	12,119	14,672
Total impaired loans
Related Allowance	(1,634)	(1,863)
Mortgage loans \| Residential \| Full documentation amortizing
With an allowance recorded:
Unpaid Principal Balance	89,948	88,106
Recorded Investment	81,243	79,584
Related Allowance	(3,373)	(3,494)
Net Investment	77,870	76,090
Total impaired loans
Related Allowance	(3,373)	(3,494)
Mortgage loans \| Residential \| Reduced documentation interest-only
With an allowance recorded:
Unpaid Principal Balance	18,646	28,637
Recorded Investment	15,673	23,090
Related Allowance	(1,367)	(1,589)
Net Investment	14,306	21,501
Total impaired loans
Related Allowance	(1,367)	(1,589)
Mortgage loans \| Residential \| Reduced documentation amortizing
With an allowance recorded:
Unpaid Principal Balance	88,981	79,670
Recorded Investment	77,591	70,623
Related Allowance	(2,317)	(2,098)
Net Investment	75,274	68,525
Without an allowance recorded:
Unpaid Principal Balance	3,123	2,965
Recorded Investment	2,695	2,595
Net Investment	2,695	2,595
Total impaired loans
Related Allowance	(2,317)	(2,098)
Mortgage loans \| Multi-family
With an allowance recorded:
Unpaid Principal Balance	1,449	2,427
Recorded Investment	1,449	2,432
Related Allowance	(1)	(24)
Net Investment	1,448	2,408
Without an allowance recorded:
Unpaid Principal Balance	5,164	5,272
Recorded Investment	4,610	4,680
Net Investment	4,610	4,680
Total impaired loans
Related Allowance	(1)	(24)
Mortgage loans \| Commercial real estate
With an allowance recorded:
Unpaid Principal Balance	2,266	0
Recorded Investment	2,266	0
Related Allowance	(70)	0
Net Investment	2,196	0
Without an allowance recorded:
Unpaid Principal Balance	10,812	11,791
Recorded Investment	9,163	10,033
Net Investment	9,163	10,033
Total impaired loans
Related Allowance	$ (70)	$ 0

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No definition available.

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

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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

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=66008989&loc=SL6953550-111524

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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
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: 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=66008989&loc=d3e5212-111524

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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
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=66008989&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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