Loans Receivable and Allowance for Loan Losses - Summary of Information Related to Impaired Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
With an allowance recorded:
Related Allowance	$ (9,378)	$ (14,813)
Without an allowance recorded:
Unpaid Principal Balance	244,574	271,192
Impaired loans	213,663	237,518
Related Allowance	(9,378)	(14,813)
Net Investment	204,285	222,705
Residential
Without an allowance recorded:
Unpaid Principal Balance	2,965	0
Recorded Investment	2,595	0
Net Investment	2,595	0
Consumer and other loans \| Home equity lines of credit
With an allowance recorded:
Unpaid Principal Balance	4,414	5,295
Recorded Investment	4,049	4,968
Related Allowance	(310)	(421)
Net Investment	3,739	4,547
Without an allowance recorded:
Related Allowance	(310)	(421)
Consumer and other loans \| Commercial and industrial
Without an allowance recorded:
Unpaid Principal Balance	90	0
Recorded Investment	42	0
Net Investment	42	0
Mortgage loans \| Residential \| Full documentation interest-only
With an allowance recorded:
Unpaid Principal Balance	21,202	37,454
Recorded Investment	16,535	30,631
Related Allowance	(1,863)	(4,051)
Net Investment	14,672	26,580
Without an allowance recorded:
Related Allowance	(1,863)	(4,051)
Mortgage loans \| Residential \| Full documentation amortizing
With an allowance recorded:
Unpaid Principal Balance	88,106	69,242
Recorded Investment	79,584	63,223
Related Allowance	(3,494)	(2,534)
Net Investment	76,090	60,689
Without an allowance recorded:
Related Allowance	(3,494)	(2,534)
Mortgage loans \| Residential \| Reduced documentation interest-only
With an allowance recorded:
Unpaid Principal Balance	28,637	55,939
Recorded Investment	23,090	46,540
Related Allowance	(1,589)	(4,253)
Net Investment	21,501	42,287
Without an allowance recorded:
Related Allowance	(1,589)	(4,253)
Mortgage loans \| Residential \| Reduced documentation amortizing
With an allowance recorded:
Unpaid Principal Balance	79,670	57,955
Recorded Investment	70,623	52,520
Related Allowance	(2,098)	(2,310)
Net Investment	68,525	50,210
Without an allowance recorded:
Related Allowance	(2,098)	(2,310)
Mortgage loans \| Multi-family
With an allowance recorded:
Unpaid Principal Balance	2,427	8,029
Recorded Investment	2,432	7,950
Related Allowance	(24)	(456)
Net Investment	2,408	7,494
Without an allowance recorded:
Unpaid Principal Balance	5,272	19,523
Recorded Investment	4,680	16,693
Net Investment	4,680	16,693
Related Allowance	(24)	(456)
Mortgage loans \| Commercial real estate
With an allowance recorded:
Unpaid Principal Balance	0	6,651
Recorded Investment	0	6,723
Related Allowance	0	(788)
Net Investment	0	5,935
Without an allowance recorded:
Unpaid Principal Balance	11,791	11,104
Recorded Investment	10,033	8,270
Net Investment	10,033	8,270
Related Allowance	$ 0	$ (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.

+ References

No definition available.

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- Definition

Impaired Financing Receivable, with No Related Allowance [Abstract]

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No definition available.

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- Definition

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+ 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=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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- Definition

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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- Definition

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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