Loans Receivable and Allowance for Loan Losses - Schedule of Loans Receivable and Related Allowance for Loan Loss Allocation (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Loans:
Individually evaluated for impairment	$ 213,663	$ 237,518
Collectively evaluated for impairment	10,166,695	10,874,209
Total loans	10,380,358	11,111,727
Allowance for loan losses:
Individually evaluated for impairment	9,378	14,813
Collectively evaluated for impairment	76,722	83,187
Total allowance for loan losses	86,100	98,000	$ 111,600	$ 139,000
Consumer and Other Loans
Loans:
Individually evaluated for impairment	4,091	4,968
Collectively evaluated for impairment	235,023	247,725
Total loans	239,114	252,693
Allowance for loan losses:
Individually evaluated for impairment	310	421
Collectively evaluated for impairment	5,151	5,867
Total allowance for loan losses	5,461	6,288	8,825	8,824
Mortgage Loans \| Residential
Loans:
Individually evaluated for impairment	192,427	192,914
Collectively evaluated for impairment	5,172,936	5,822,501
Total loans	5,365,363	6,015,415
Allowance for loan losses:
Individually evaluated for impairment	9,044	13,148
Collectively evaluated for impairment	27,395	31,803
Total allowance for loan losses	36,439	44,951	46,283	80,337
Mortgage Loans \| Multi- Family
Loans:
Individually evaluated for impairment	7,112	24,643
Collectively evaluated for impairment	4,039,510	3,999,462
Total loans	4,046,622	4,024,105
Allowance for loan losses:
Individually evaluated for impairment	24	456
Collectively evaluated for impairment	34,877	35,088
Total allowance for loan losses	34,901	35,544	39,250	36,703
Mortgage Loans \| Commercial Real Estate
Loans:
Individually evaluated for impairment	10,033	14,993
Collectively evaluated for impairment	719,226	804,521
Total loans	729,259	819,514
Allowance for loan losses:
Individually evaluated for impairment	0	788
Collectively evaluated for impairment	9,299	10,429
Total allowance for loan losses	$ 9,299	$ 11,217	$ 17,242	$ 13,136

Financing Receivable, Allowance for Credit Losses, Evaluated for Impairment [Abstract]

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Financing Receivable, Evaluated for Impairment [Abstract]

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for 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 11B
-Subparagraph (g)
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
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-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section L
-Subsection 1

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Amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. Excludes amounts related to receivables held-for-sale.

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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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