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Rollforward of Financial Instruments Classified in Level Three of Valuation Hierarchy (Detail) - USD ($) $ in Thousands | 6 Months Ended
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Jun. 30, 2018 | Jun. 30, 2017
Interest rate lock commitments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair Value, Beginning Balance |  | $ 982
Total Realized/Unrealized (Losses)/Gains Recorded in (Loss)/ Income |  | 45
Total Realized/Unrealized (Losses)/Gain Recorded in Comprehensive (Loss) Income |  | 0
Settlements |  | 0
Transfers to/(from) level 3 |  | 0
Fair Value, Ending Balance |  | 1,027
Change in Unrealized Gains/(Losses) Related to Instruments Held |  | 1,027
Mortgage servicing rights |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Fair Value, Beginning Balance | $ 2,729 | 228,099
Total Realized/Unrealized (Losses)/Gains Recorded in (Loss)/ Income | (224) | (19,496)
Total Realized/Unrealized (Losses)/Gain Recorded in Comprehensive (Loss) Income | 0 | 0
Issuances |  | 11,983
Settlements | 0 | 0
Transfers to/(from) level 3 | 0 | 0
Fair Value, Ending Balance | 2,505 | 220,586
Change in Unrealized Gains/(Losses) Related to Instruments Held | $ (224) | $ (10,348)

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- Definition Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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- Definition Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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