Loans Receivable and Allowance for Loan Losses - Schedule of Change in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for Loan and Lease Losses
Beginning balance	$ 98,000	$ 111,600	$ 139,000
Provision (credited) charged to operations	(9,151)	(12,072)	(9,469)
Charge-offs	(10,191)	(8,270)	(29,589)
Recoveries	7,442	6,742	11,658
Ending balance	86,100	98,000	111,600
Consumer and Other Loans
Allowance for Loan and Lease Losses
Beginning balance	6,288	8,825	8,824
Provision (credited) charged to operations	(326)	(2,002)	1,709
Charge-offs	(1,364)	(912)	(2,073)
Recoveries	863	377	365
Ending balance	5,461	6,288	8,825
Mortgage Loans \| Residential
Allowance for Loan and Lease Losses
Beginning balance	44,951	46,283	80,337
Provision (credited) charged to operations	(3,980)	1,520	(23,464)
Charge-offs	(7,977)	(6,149)	(19,868)
Recoveries	3,445	3,297	9,278
Ending balance	36,439	44,951	46,283
Mortgage Loans \| Multi- Family
Allowance for Loan and Lease Losses
Beginning balance	35,544	39,250	36,703
Provision (credited) charged to operations	(2,387)	(4,780)	5,337
Charge-offs	(409)	(907)	(4,365)
Recoveries	2,153	1,981	1,575
Ending balance	34,901	35,544	39,250
Mortgage Loans \| Commercial Real Estate
Allowance for Loan and Lease Losses
Beginning balance	11,217	17,242	13,136
Provision (credited) charged to operations	(2,458)	(6,810)	6,949
Charge-offs	(441)	(302)	(3,283)
Recoveries	981	1,087	440
Ending balance	$ 9,299	$ 11,217	$ 17,242

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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- Definition

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)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section L
-Subsection 1

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Amount of expense related to estimated loss from loan and lease transactions.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
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-Subparagraph (SX 210.9-04.11)
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