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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 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 + Details
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