Acquisitions - Pro Forma Results (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($)
Pro forma results of operations
Net operating revenues	$ 1,300,544
Net income attributable to the Company	34,538
U.S. HealthWorks
Acquisition costs
U.S. HealthWorks acquisition costs	$ (2,900)

Business Acquisition, Pro Forma Net Income (Loss) Attributable To Parent

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- Definition

Represents acquisition costs excluded from proforma results.

+ References

No definition available.

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
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