Long-Term Debt and Notes Payable - Principal Maturities Of Long-Term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
2020	$ 14,318
2021	8,130
2022	17,215
2023	8,121
2024	199,700
Thereafter	3,324,570
Total	3,572,054	$ 3,447,221
Other debt, including finance leases
Debt Instrument [Line Items]
2020	14,318
2021	8,130
2022	17,215
2023	3,364
2024	23,550
Thereafter	12,040
Total	$ 78,617	78,941
Select Medical Corporation \| Senior Notes
Debt Instrument [Line Items]
Interest rate of debt (as a percent)	6.25%
2020	$ 0
2021	0
2022	0
2023	0
2024	0
Thereafter	1,225,000
Total	1,225,000	1,225,000
Select Medical Corporation \| Credit facilities \| Revolving facility
Debt Instrument [Line Items]
2020	0
2021	0
2022	0
2023	0
2024	165,000
Thereafter	0
Total	165,000	0
Select Medical Corporation \| Term loans
Debt Instrument [Line Items]
2020	0
2021	0
2022	0
2023	4,757
2024	11,150
Thereafter	2,087,530
Total	$ 2,103,437	$ 2,143,280

Long-Term Debt And Finance Lease Obligation, Maturities, Repayments Of Principal After Year Five

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Long-Term Debt And Finance Lease Obligation, Maturities, Repayments Of Principal In Year Five

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Long-Term Debt And Finance Lease Obligation, Maturities, Repayments Of Principal In Year Four

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Long-Term Debt And Finance Lease Obligation, Maturities, Repayments Of Principal In Year Three

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Long-Term Debt And Finance Lease Obligation, Maturities, Repayments Of Principal In Year Two

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Long-Term Debt And Finance Lease Obligation, Repayments Of Principal, Remainder Of Fiscal Year

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Long-Term Debt, Gross And Finance Lease Obligation

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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