Business Acquisition, Equity Interest Issued or Issuable, Percentage

No definition available.

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- Definition

Line Of Credit Facility, Additional Borrowing Capacity

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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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

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

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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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

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
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Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=sem_TermLoanFacilityMember
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Period Type:

- Details

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- Details

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- Details

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- Details

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Subsequent Events (Details) - USD ($)				12 Months Ended
Subsequent Events (Details) - USD ($)	Feb. 01, 2018	Oct. 23, 2017	Jun. 01, 2015	Dec. 31, 2017
Credit facility \| Concentra Inc
Subsequent Event
Maximum borrowing capacity			$ 500,000,000
Credit facility \| Revolving facility \| Concentra Inc
Subsequent Event
Maximum borrowing capacity			$ 50,000,000
Debt instrument term (in years)			5 years
Credit facility \| Term loan \| Concentra Inc
Subsequent Event
Debt instrument term (in years)			7 years
Aggregate principal amount			$ 450,000,000.0
Credit facility \| Adjusted LIBO \| Term loan \| Concentra Inc
Subsequent Event
Interest rate margin (as a percent)			3.00%
Credit facility \| Adjusted LIBO Rate floor \| Term loan \| Concentra Inc
Subsequent Event
Interest rate margin (as a percent)			1.00%
Credit facility \| Alternate Base Rate \| Term loan \| Concentra Inc
Subsequent Event
Interest rate margin (as a percent)			2.00%
Credit facility \| Alternate Base Rate floor \| Term loan \| Concentra Inc
Subsequent Event
Interest rate margin (as a percent)			2.00%
Credit facility \| Second Lien Credit Agreement \| Term loan \| Concentra Inc
Subsequent Event
Debt instrument term (in years)			8 years
Aggregate principal amount			$ 200,000,000.0
Credit facility \| Second Lien Credit Agreement \| Adjusted LIBO \| Term loan \| Concentra Inc
Subsequent Event
Interest rate margin (as a percent)			8.00%
Credit facility \| Second Lien Credit Agreement \| Adjusted LIBO Rate floor \| Term loan \| Concentra Inc
Subsequent Event
Interest rate margin (as a percent)			1.00%
Credit facility \| Second Lien Credit Agreement \| Alternate Base Rate \| Term loan \| Concentra Inc
Subsequent Event
Interest rate margin (as a percent)			7.00%
Credit facility \| Second Lien Credit Agreement \| Alternate Base Rate floor \| Term loan \| Concentra Inc
Subsequent Event
Interest rate margin (as a percent)			2.00%
Subsequent Event \| Credit facility \| Revolving facility \| Concentra Inc
Subsequent Event
Additional borrowing capacity	$ 25,000,000
Subsequent Event \| Credit facility \| Term loan \| Concentra Inc
Subsequent Event
Additional borrowing capacity	$ 555,000,000
Subsequent Event \| Credit facility \| Adjusted LIBO \| Term loan \| Concentra Inc
Subsequent Event
Interest rate margin (as a percent)	2.75%
Subsequent Event \| Credit facility \| Adjusted LIBO Rate floor \| Term loan \| Concentra Inc
Subsequent Event
Interest rate margin (as a percent)	1.00%
Subsequent Event \| Credit facility \| Alternate Base Rate \| Term loan \| Concentra Inc
Subsequent Event
Interest rate margin (as a percent)	1.75%
Subsequent Event \| Credit facility \| Alternate Base Rate floor \| Term loan \| Concentra Inc
Subsequent Event
Interest rate margin (as a percent)	2.00%
Subsequent Event \| Credit facility \| Second Lien Credit Agreement \| Term loan \| Concentra Inc
Subsequent Event
Aggregate principal amount	$ 240,000,000
Subsequent Event \| Credit facility \| Second Lien Credit Agreement \| Adjusted LIBO \| Term loan \| Concentra Inc
Subsequent Event
Interest rate margin (as a percent)	6.50%
Subsequent Event \| Credit facility \| Second Lien Credit Agreement \| Adjusted LIBO Rate floor \| Term loan \| Concentra Inc
Subsequent Event
Interest rate margin (as a percent)	1.00%
Subsequent Event \| Credit facility \| Second Lien Credit Agreement \| Alternate Base Rate \| Term loan \| Concentra Inc
Subsequent Event
Interest rate margin (as a percent)	5.50%
Subsequent Event \| Credit facility \| Second Lien Credit Agreement \| Alternate Base Rate floor \| Term loan \| Concentra Inc
Subsequent Event
Interest rate margin (as a percent)	2.00%
U.S Health Works
Subsequent Event
Acquisition costs				$ 2,800,000
Consideration transferred		$ 753,000,000
U.S Health Works \| Concentra Group Holdings Parent
Subsequent Event
Voting equity interests issued		20.00%
Value of equity interest		$ 238,000,000