Represents the issue price as a percentage of the principal amount of debt instrument.

No definition available.

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- Definition

Represents the redemption price as a percentage of the principal amount at which the debt instrument may be required to be repurchased in the event of a change of control by the entity.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

+ Details

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- Definition

The cash inflow from borrowings supported by a written promise to pay an obligation that is collateralized (backed by pledge, mortgage or other lien in the entity's assets).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

+ Details

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Balance Type:	debit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Long-Term Debt and Notes Payable - Senior Notes (Details) - Select Excluding Concentra - Senior notes - USD ($)		12 Months Ended
	Mar. 11, 2014	Dec. 31, 2017	Mar. 06, 2017	Dec. 31, 2016	May 28, 2013
Debt Instrument, Redemption, Period One
Long-term debt and notes payable
Redemption price		103.188%
Debt Instrument, Redemption, Period Two
Long-term debt and notes payable
Redemption price		101.594%
Debt Instrument, Redemption, Period Three
Long-term debt and notes payable
Redemption price		100.00%
6.375% Senior Notes Due June 2021
Long-term debt and notes payable
Aggregate principal amount					$ 600,000,000.0
Interest rate of debt (as a percent)		6.375%	6.375%	6.375%	6.375%
Percentage of principal amount at which notes may be required to be repurchased in event of change of control by the entity		101.00%
Additional Notes
Long-term debt and notes payable
Aggregate principal amount	$ 110,000,000.0
Interest rate of debt (as a percent)	6.375%
Issue price (as a percent)	101.50%
Gross proceeds	$ 111,700,000