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Derivatives - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 | Mar. 31, 2017 | Dec. 13, 2017
Option Indexed to Issuer's Equity [Line Items] |  |  |
Replacement cost of contracts in a gain position | $ 24.7 |  | $ 12.7
Change in fair value of rate lock commitments, net | 15.1 | $ 2.1 |
Rate Lock Commitments [Member] |  |  |
Option Indexed to Issuer's Equity [Line Items] |  |  |
Change in fair value of rate lock commitments, net | $ 2.5 | $ 0.8 |

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- Definition For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 30 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14172-108612 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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