Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980

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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

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of required minimum payments for employee agreements in excess of one year due in the next fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

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- Definition

Amount of required minimum payments for employee agreements in excess of one year due after next fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

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Namespace Prefix:	usph_
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Balance Type:	credit
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- Definition

Expiration date of the employment agreements.

+ References

No definition available.

+ Details

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- Definition

Number of employees covered under employee agreement during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

Employment agreement renewal period.

+ References

No definition available.

+ Details

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Balance Type:	na
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Commitments and Contingencies (Details) $ in Millions	12 Months Ended
Commitments and Contingencies (Details) $ in Millions	Dec. 31, 2017 USD ($) Officer	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Operating Leased Assets [Line Items]
Rent expense	$ 34.8	$ 30.3	$ 28.3
Renewal period of employment agreements	2 years
Expiration date	Dec. 31, 2018
Future compensation - 2018	$ 30.1
Future compensation - 2019 through 2022	$ 15.6
Executive Officer [Member]
Operating Leased Assets [Line Items]
Number of officers with the company had employee agreement \| Officer	3
Minimum [Member]
Operating Leased Assets [Line Items]
Operating leases renewal period	1 year
Maximum [Member]
Operating Leased Assets [Line Items]
Operating leases renewal period	5 years