U.K. Sale - Result of Operation (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($)
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Loss from discontinued operations, net of taxes	$ (12,641)
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
Salaries, wages and benefits	35,937
Professional fees	6,815
Supplies	2,217
Rents and leases	2,509
Other operating expenses	6,682
Interest expense, net	10
Loss on sale	13,490
Transaction-related expenses	6,265
Total expenses	73,925
Loss from discontinued operations before income taxes	(11,405)
Benefit from income taxes	1,236
Loss from discontinued operations, net of taxes	$ (12,641)

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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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