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Off-Balance-Sheet Originate Loans and Letters of Credit (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Commitments and Contingencies Disclosure [Line Items]
Commitments	$ 2,274,678
Total loans
Commitments and Contingencies Disclosure [Line Items]
Commitments	1,935,275	$ 2,100,000
Commercial, performance stand-by, and financial stand-by letters of credit
Commitments and Contingencies Disclosure [Line Items]
Commitments	339,403	$ 324,300
Total mortgage loan commitments
Commitments and Contingencies Disclosure [Line Items]
Commitments	621,105
Total mortgage loan commitments | Multifamily and Commercial Real Estate
Commitments and Contingencies Disclosure [Line Items]
Commitments	377,782
Total mortgage loan commitments | One-to-four family
Commitments and Contingencies Disclosure [Line Items]
Commitments	3,819
Total mortgage loan commitments | Acquisition, Development and Construction
Commitments and Contingencies Disclosure [Line Items]
Commitments	239,504
Other loan commitments
Commitments and Contingencies Disclosure [Line Items]
Commitments	$ 1,314,170

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- Definition

Commitments and Contingencies Disclosure [Line Items]

+ References

No definition available.

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Fair value portion of arrangements with third parties, including, but not limited to, operating lease arrangement and arrangement in which the entity has agreed to expend funds to procure goods or services, or has agreed to commit resources to supply goods or services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(25))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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