Disposal group including discontinued operation impairment loss.

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Disposal group including discontinued operation interest expense net.

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Disposal group including discontinued operation professional fees.

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Disposal group including discontinued operation rents and leases.

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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 of depreciation and amortization expense attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of operating expense attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of other expense attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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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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U.K. Sale - Result of Operation (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
(Loss) income from discontinued operations	$ (828,697)	$ (7,502)	$ 10,993	$ 12,816	$ 1,879	$ 17,803	$ 21,237	$ 15,893	$ (812,390)	$ 56,812	$ (232,974)
Discontinued Operations [Member] \| U.K. Sales [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue									1,119,768	1,099,081	1,107,747
Salaries, wages and benefits									632,134	609,823	610,031
Professional fees									127,291	122,532	117,376
Supplies									38,285	37,527	37,852
Rents and leases									47,748	46,743	45,967
Other operating expenses									113,534	115,897	110,827
Depreciation and amortization									74,935	76,121	78,490
Interest expense, net									(417)	(231)	876
Loss on sale									867,324
Loss on impairment									20,239	27,169	337,889
Transaction-related expenses									8,719	5,907	4,788
Total expenses									1,929,792	1,041,488	1,344,096
(Loss) income from discontinued operations before income taxes									(810,024)	57,593	(236,349)
Provision for (benefit from) income taxes									2,366	781	(3,375)
(Loss) income from discontinued operations									$ (812,390)	$ 56,812	$ (232,974)