Commitments and Contingencies - Additional Information (Detail) £ in Millions		1 Months Ended	6 Months Ended		12 Months Ended
	Jul. 09, 2020 USD ($)	Jul. 31, 2019 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2020 GBP (£)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Jun. 30, 2020 GBP (£)	Jun. 01, 2020 USD ($)	Mar. 31, 2020 USD ($)	Jan. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Commitments and Contingencies Disclosure [Line Items]
Self-insured for professional and general liability, current			$ 42,000,000											$ 42,000,000
Compensation liability claims			90,000,000											81,000,000
Compensation and related benefits			40,000,000											40,000,000
Amount of remaining settlement agreements			6,000,000.0
Accrued interest on settlement amount			$ 230,000
Corporate integrity agreement			5 years	5 years
Department of Human Services
Commitments and Contingencies Disclosure [Line Items]
Aggregate payment made					$ 4,000,000	$ 4,000,000	$ 4,000,000	$ 4,000,000	$ 4,000,000
Amount claimed from over payments of legal settlements					7,000,000	8,000,000	7,000,000	$ 4,000,000
Amount claimed from over payments of legal settlements due to change in calculations					3,000,000	2,000,000	2,000,000
River Point Behavioral Health
Commitments and Contingencies Disclosure [Line Items]
Amount withheld in contingent Medicare payment suspension			$ 9,700,000
Subsequent Event
Commitments and Contingencies Disclosure [Line Items]
Aggregate payment made	$ 117,300,000
DOJ
Commitments and Contingencies Disclosure [Line Items]
Definitive settlement and related civil agreements		$ 127,000,000
Pre-tax reserve												$ 134,000,000		134,000,000
DOJ | Subsequent Event
Commitments and Contingencies Disclosure [Line Items]
Aggregate payment made	88,100,000
US District Court for District Of Massachusetts | Subsequent Event
Commitments and Contingencies Disclosure [Line Items]
Aggregate payment made	10,000,000.0
Per Occurrence/Per Location Deductible | Wind Storms
Commitments and Contingencies Disclosure [Line Items]
Commercial property insurance policies covering catastrophic losses											$ 2,500,000
OTHER STATES | Subsequent Event
Commitments and Contingencies Disclosure [Line Items]
Aggregate payment made	$ 28,900,000
Cygnet Health Care Limited
Commitments and Contingencies Disclosure [Line Items]
Property insurance | £				£ 1,500
Maximum
Commitments and Contingencies Disclosure [Line Items]
Percentage of accrued interest on the settlement amounts			1.25%	1.25%
Maximum | Wind Storms
Commitments and Contingencies Disclosure [Line Items]
Commercial property insurance policies covering catastrophic losses			$ 1,000,000,000
Percentage of insurance deductible			5.00%							5.00%
Maximum | Flood
Commitments and Contingencies Disclosure [Line Items]
Commercial property insurance policies covering catastrophic losses			$ 100,000,000
Maximum | LAS VEGAS, NEVADA | Earthquake
Commitments and Contingencies Disclosure [Line Items]
Commercial property insurance policies covering catastrophic losses			500,000,000
Maximum | CALIFORNIA | Earthquake
Commitments and Contingencies Disclosure [Line Items]
Commercial property insurance policies covering catastrophic losses			130,000,000
Maximum | Faulty Zones of UNITED STATES | Earthquake
Commitments and Contingencies Disclosure [Line Items]
Commercial property insurance policies covering catastrophic losses			100,000,000
Maximum | PUERTO RICO | Earthquake
Commitments and Contingencies Disclosure [Line Items]
Commercial property insurance policies covering catastrophic losses			40,000,000
Maximum | PUERTO RICO | Flood
Commitments and Contingencies Disclosure [Line Items]
Commercial property insurance policies covering catastrophic losses			1,000,000
Maximum | OTHER STATES | Earthquake
Commitments and Contingencies Disclosure [Line Items]
Commercial property insurance policies covering catastrophic losses			250,000,000
Maximum | Texas | Flood
Commitments and Contingencies Disclosure [Line Items]
Commercial property insurance policies covering catastrophic losses			$ 10,000,000
Minimum
Commitments and Contingencies Disclosure [Line Items]
Percentage of accrued interest on the settlement amounts			2.125%	2.125%
Minimum | Wind Storms
Commitments and Contingencies Disclosure [Line Items]
Percentage of insurance deductible			3.00%							3.00%
General And Professional Liability Insurance Policies
Commitments and Contingencies Disclosure [Line Items]
Self-insured for professional and general liability			$ 20,000,000
General and Professional Liability
Commitments and Contingencies Disclosure [Line Items]
Self-insured for professional and general liability			$ 250,000,000											242,000,000
Subsidiaries | Professional Liability
Commitments and Contingencies Disclosure [Line Items]
Self-insured for professional and general liability														5,000,000	$ 5,000,000	$ 5,000,000
Purchased several excess policies through commercial insurance carriers per occurrence													$ 2,500,000
Purchased several excess policies through commercial insurance carriers per occurrence excess claim amount													10,000,000
Subsidiaries | Professional Liability | Cygnet Health Care Limited
Commitments and Contingencies Disclosure [Line Items]
Self-insured for professional and general liability | £										£ 10
Subsidiaries | Professional Liability | Maximum
Commitments and Contingencies Disclosure [Line Items]
Self-insured for professional and general liability													10,000,000				$ 10,000,000
Subsidiaries | General Liability
Commitments and Contingencies Disclosure [Line Items]
Self-insured for professional and general liability														$ 3,000,000	$ 3,000,000	$ 3,000,000
Subsidiaries | General Liability | Cygnet Health Care Limited
Commitments and Contingencies Disclosure [Line Items]
Self-insured for professional and general liability | £										£ 25
Subsidiaries | General Liability | Maximum
Commitments and Contingencies Disclosure [Line Items]
Self-insured for professional and general liability													$ 3,000,000				$ 3,000,000
Subsidiaries | General And Professional Liability Insurance Policies
Commitments and Contingencies Disclosure [Line Items]
Percentage of liability for claims paid under commercially insured coverage			10.00%							10.00%
Subsidiaries | General And Professional Liability Insurance Policies | Maximum
Commitments and Contingencies Disclosure [Line Items]
Purchased several excess policies through commercial insurance carriers per occurrence					$ 250,000,000	$ 250,000,000	$ 200,000,000
Liability for claims paid under commercially insured coverage			$ 5,000,000
Subsidiaries | General And Professional Liability Insurance Policies | Maximum | Located in U.K.
Commitments and Contingencies Disclosure [Line Items]
Liability for claims paid under commercially insured coverage			$ 8,500,000