U.K. Sale - Result of Operation (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
(Loss) income from discontinued operations	$ (12,641)	$ 15,089
Discontinued Operations [Member] \| U.K. Sales [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue	62,520	273,593
Salaries, wages and benefits	35,937	153,329
Professional fees	6,815	32,249
Supplies	2,217	9,775
Rents and leases	2,509	11,707
Other operating expenses	6,682	30,373
Depreciation and amortization		18,845
Interest expense, net	10	220
Loss on sale	14,254
Transaction-related expenses	6,265	2,023
Total expenses	74,689	258,521
(Loss) income from discontinued operations before income taxes	(12,169)	15,072
Provision for (benefit from) income taxes	472	(17)
(Loss) income from discontinued operations	$ (12,641)	$ 15,089

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Disposal group including discontinued operation salaries wages and benefits.

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Disposal group including discontinued operation supplies.

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Disposal group including discontinued operation transaction-related expenses.

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Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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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.

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