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Fair Value of Financial Assets and Liabilities - Roll forward of Derivative Instruments and Contingent Consideration Require Valuation Based upon Significant Unobservable Inputs (Detail) - Level 3 [Member] - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2018 | Mar. 31, 2017
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Opening Balance | $ 27,340 | $ 48,967
Total realized and unrealized (gains) losses included in Net income | 7,170 | 2,900
Settlements | (4,387) | (20,407)
Closing Balance | 30,123 | 31,460
Unrealized (gains) losses outstanding | 7,170 | 2,900
Contingent Consideration [Member] |  |
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Opening Balance | 23,711 | 38,713
Total realized and unrealized (gains) losses included in Net income | 134 | 438
Settlements | (758) | (10,153)
Closing Balance | 23,087 | 28,998
Unrealized (gains) losses outstanding | 134 | 438
Rate Lock Commitments and Forwards, Net [Member] |  |
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Opening Balance | 3,629 | 10,254
Total realized and unrealized (gains) losses included in Net income | 7,036 | 2,462
Settlements | (3,629) | (10,254)
Closing Balance | 7,036 | 2,462
Unrealized (gains) losses outstanding | $ 7,036 | $ 2,462

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- Definition Fair value measurement with unobservable inputs reconciliation recurring basis liability net, unrealized gain (loss). + References No definition available. + 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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- Definition Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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