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Forgivable loans, forgiveness period, maximum

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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Amount of expense for amortization of capitalized computer software costs.

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Unamortized costs incurred for development of computer software, which is to be sold, leased or otherwise marketed, after establishing technological feasibility through to the general release of the software products. Excludes capitalized costs of developing software for internal use.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property by the lessor or lessee, respectively.

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Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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Research and development expense during the period related to the costs of developing and achieving technological feasibility of a computer software product to be sold, leased, or otherwise marketed.

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Description of Business and Summary of Significant Accounting Policies (Detail)	12 Months Ended
	Dec. 31, 2018 USD ($) segment	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Aug. 20, 2018 USD ($)
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Number of reportable business segments \| segment	5
Research and development costs related to software development	$ 8,700,000	$ 14,900,000	$ 17,500,000
Advertising costs	15,500,000	14,800,000	15,900,000
Provision for doubtful accounts	$ 17,872,000	15,386,000	8,912,000
Forgivable loans, forgiveness period, minimum	2 years
Forgivable loans, forgiveness period, maximum	10 years
Definite-lived intangible assets amortization period	14 years 2 months 12 days
Unamortized capitalized software cost	$ 200,000	14,800,000
Amortization of capitalized software cost	5,300,000	6,700,000	$ 12,000,000
Deferred rent	$ 45,100,000	$ 43,900,000
Minimum
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Definite-lived intangible assets amortization period	5 years
Maximum
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Definite-lived intangible assets amortization period	15 years
Lease provisions for renewal options	5 years
Furniture, Equipment, And Internal-Use Software \| Minimum
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Estimated useful of furniture, equipment and internal use software (in years)	3 years
Furniture, Equipment, And Internal-Use Software \| Maximum
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Estimated useful of furniture, equipment and internal use software (in years)	7 years
Software and Software Development Costs
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Estimated useful of furniture, equipment and internal use software (in years)	3 years
Geographic Concentration Risk \| Consolidated Revenues \| Non U.S
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Revenue from the work of professionals	32.00%
Senior Notes \| Convertible Note Due 2023
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Interest rate (as a percent)				2.00%
Principal amount				$ 316,300,000.0