Long-Term Debt and Notes Payable - Principal Maturities Of Long-Term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
2019	$ 10,906
2020	27,965
2021	712,111
2022	1,300,656
2023	240,362
Thereafter	1,061,091
Total	3,353,091	$ 3,338,381
Select Medical Corporation
Debt Instrument [Line Items]
2019	9,262
2020	27,211
2021	711,781
2022	160,000
2023	0
Thereafter	1,057,622
Total	$ 1,965,876	1,916,290
Select Medical Corporation \| Senior notes \| 6.375% Senior Notes Due June 2021
Debt Instrument [Line Items]
Interest rate of debt (as a percent)	6.375%
2019	$ 0
2020	0
2021	710,000
2022	0
2023	0
Thereafter	0
Total	710,000	710,000
Select Medical Corporation \| Credit facilities \| Revolving facility
Debt Instrument [Line Items]
2019	0
2020	0
2021	0
2022	160,000
2023	0
Thereafter	0
Total	160,000	20,000
Select Medical Corporation \| Credit facilities \| Term loans
Debt Instrument [Line Items]
2019	0
2020	0
2021	0
2022	0
2023	0
Thereafter	1,031,068
Total	1,031,068	1,129,875
Select Medical Corporation \| Other debt, including finance leases
Debt Instrument [Line Items]
2019	9,262
2020	27,211
2021	1,781
2022	0
2023	0
Thereafter	26,554
Total	64,808	56,415
Concentra Inc
Debt Instrument [Line Items]
2019	1,644
2020	754
2021	330
2022	1,140,656
2023	240,362
Thereafter	3,469
Total	1,387,215	1,422,091
Concentra Inc \| Credit facilities \| Term loans
Debt Instrument [Line Items]
2019	0
2020	0
2021	0
2022	1,140,298
2023	239,999
Thereafter	0
Total	1,380,297	1,414,175
Concentra Inc \| Other debt, including finance leases
Debt Instrument [Line Items]
2019	1,644
2020	754
2021	330
2022	358
2023	363
Thereafter	3,469
Total	$ 6,918	$ 7,916

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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