Represents the amount of term loans which converted to another series with different maturity dates and interest rates.

No definition available.

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Namespace Prefix:	sem_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the leverage ratio as defined in the credit facility agreement

+ References

No definition available.

+ Details

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Namespace Prefix:	sem_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the premium for term loans prepayments.

+ References

No definition available.

+ Details

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Namespace Prefix:	sem_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the quarterly required periodic payments applied to principal (as a percentage of principal).

+ References

No definition available.

+ Details

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Namespace Prefix:	sem_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the prepayment of principal amount of debt instrument from excess cash flow, as required under the terms of the credit agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	sem_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the borrowing capacity of the incremental revolving commitments under the credit extension amendment.

+ References

No definition available.

+ Details

Name:	sem_LineOfCreditFacilityIncreaseinMaximumBorrowingCapacity
Namespace Prefix:	sem_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

Name:	us-gaap_LineOfCreditFacilityLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_ConsolidatedEntitiesAxis=sem_SelectExcludingConcentraMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=sem_A2011SelectCreditFacilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=sem_TermLoanFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=sem_SeriesETrancheBTermLoansMember
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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=sem_DebtInstrumentVariableRateBaseAdjustedLIBOMember
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Data Type:	na
Balance Type:
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- Details

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- Details

Name:	us-gaap_VariableRateAxis=us-gaap_BaseRateMember
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Data Type:	na
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- Details

Name:	us-gaap_DebtInstrumentAxis=sem_SeriesFTrancheBTermLoansMember
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Long-Term Debt and Notes Payable - 2011 Select Credit Facilities (Details) - Credit facility - Select Excluding Concentra						3 Months Ended	9 Months Ended
	Mar. 04, 2016 USD ($)	Mar. 02, 2016 USD ($)	Dec. 11, 2015 USD ($)	Dec. 10, 2015	Mar. 04, 2015 USD ($)	Dec. 31, 2015	Sep. 30, 2015	May 20, 2015 USD ($)
2011 Select Credit Facilities
Line of Credit Facility [Line Items]
Leverage ratio of financial maintenance covenant						5.75	5.00
Revolving facility
Line of Credit Facility [Line Items]
Amount of incremental revolving commitments								$ 100,000,000
Maximum borrowing capacity			$ 450,000,000
Term loan \| 2011 Select Credit Facilities
Line of Credit Facility [Line Items]
Principal prepayments from excess cash flow		$ 10,200,000			$ 26,900,000
Term loan \| 2011 Select Credit Facilities, Series E Tranche B Term Loans
Line of Credit Facility [Line Items]
Term loan conversion			$ 56,200,000
Term loan \| 2011 Select Credit Facilities, Series E Tranche B Term Loans \| Adjusted LIBO
Line of Credit Facility [Line Items]
Interest rate margin (as a percent)	5.00%		4.00%	2.75%
Term loan \| 2011 Select Credit Facilities, Series E Tranche B Term Loans \| Adjusted LIBO Rate floor
Line of Credit Facility [Line Items]
Interest rate margin (as a percent)	1.00%		1.00%	1.00%
Term loan \| 2011 Select Credit Facilities, Series E Tranche B Term Loans \| Alternate Base Rate
Line of Credit Facility [Line Items]
Interest rate margin (as a percent)	4.00%		3.00%	1.75%
Term loan \| 2011 Select Credit Facilities, Series F Tranche B Term Loans
Line of Credit Facility [Line Items]
Aggregate principal amount	$ 625,000,000
Prepayment premium (as a percent)	1.00%
Principal payments, quarterly installments (as a percent)	0.25%
Term loan \| 2011 Select Credit Facilities, Series F Tranche B Term Loans \| Adjusted LIBO
Line of Credit Facility [Line Items]
Interest rate margin (as a percent)	5.00%
Term loan \| 2011 Select Credit Facilities, Series F Tranche B Term Loans \| Adjusted LIBO Rate floor
Line of Credit Facility [Line Items]
Interest rate margin (as a percent)	1.00%
Term loan \| 2011 Select Credit Facilities, Series F Tranche B Term Loans \| Alternate Base Rate
Line of Credit Facility [Line Items]
Interest rate margin (as a percent)	4.00%