Value of input used to measure contingent consideration liability from business combination.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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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

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Fair value 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
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-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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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.

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Fair Value of Financial Assets and Liabilities - Quantitative Information about Level 3 Fair Value Measurements (Detail) $ in Thousands	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets	$ 73,448	$ 80,464	$ 92,528	$ 49,975	$ 18,437	$ 6,676
Liabilities	68,401	46,143	49,230	36,160	34,489	26,757
Contingent Consideration [Member] \| Accounts Payable, Accrued and Other Liabilities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities	$ 38,712	31,357	$ 32,552	21,574	23,088	23,710
Contingent Consideration [Member] \| Accounts Payable, Accrued and Other Liabilities [Member] \| Minimum [Member] \| Measurement Input, Discount Rate [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Unobservable Inputs	0.003		0.003
Contingent Consideration [Member] \| Accounts Payable, Accrued and Other Liabilities [Member] \| Minimum [Member] \| Measurement Input, Probability of Meeting Earnout and Contingencies [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Unobservable Inputs	0.99		0.99
Contingent Consideration [Member] \| Accounts Payable, Accrued and Other Liabilities [Member] \| Maximum [Member] \| Measurement Input, Discount Rate [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Unobservable Inputs	0.104		0.104
Contingent Consideration [Member] \| Accounts Payable, Accrued and Other Liabilities [Member] \| Maximum [Member] \| Measurement Input, Probability of Meeting Earnout and Contingencies [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Unobservable Inputs	1.00		1.00
Contingent Consideration [Member] \| Accounts Payable, Accrued and Other Liabilities [Member] \| Weighted Average [Member] \| Measurement Input, Discount Rate [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Unobservable Inputs	0.081		0.082
Contingent Consideration [Member] \| Accounts Payable, Accrued and Other Liabilities [Member] \| Weighted Average [Member] \| Measurement Input, Probability of Meeting Earnout and Contingencies [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Unobservable Inputs	0.995		0.996
Forward Contracts [Member] \| NASDAQ [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets	$ 48,652	64,290	$ 77,619	19,085
Forward Contracts [Member] \| NASDAQ [Member] \| Minimum [Member] \| Volatility [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Unobservable Inputs	0.2775		0.237
Forward Contracts [Member] \| NASDAQ [Member] \| Maximum [Member] \| Volatility [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Unobservable Inputs	0.3525		0.348
Forward Contracts [Member] \| NASDAQ [Member] \| Weighted Average [Member] \| Volatility [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Unobservable Inputs	0.322		0.302
Forward Sale Contracts [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets	$ 2,845	5,964	$ 8,177	16,442	9,687	3,753
Liabilities	27,261	9,596	9,208	641	2,421	657
Rate Lock Commitments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets	21,951	10,210	6,732	14,448	8,750	2,923
Liabilities	$ 2,428	$ 5,190	$ 7,470	$ 13,945	$ 8,980	$ 2,390