Percentage of voting equity interests acquired at the acquisition date in the business combination.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

+ Details

Name:	us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Minimum period the individual is required to perform services to be fully vested under the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6409961&loc=d3e20487-108367

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

+ Details

Name:	us-gaap_DeferredCompensationArrangementWithIndividualRequisiteServicePeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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

- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I)
-URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319

+ Details

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

- Definition

The amount of interest expense on prepetition obligations included in the statement of operations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=114872137&loc=d3e55733-112764

+ Details

Name:	us-gaap_InterestExpenseOnPrepetitionLiabilitiesRecognizedInStatementOfOperations
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfBusinessesAcquired
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfStatesInWhichEntityOperates
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

Name:	us-gaap_PropertyPlantAndEquipmentUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount that is required to be paid, determined under the conditions specified in the contract, if as of the reporting date, the holder of the share has exercised the right to or the shares are mandatorily redeemable after one year from the reporting date or operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109262807&loc=d3e22047-110879

+ Details

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

- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

+ Details

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

- Definition

Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

+ Details

Name:	us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

Name:	usph_BasisOfPresentationAbstract
Namespace Prefix:	usph_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of businesses merged during the period.

+ References

No definition available.

+ Details

Name:	usph_NumberOfBusinessesMerged
Namespace Prefix:	usph_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of clinics consolidated with the existing clinics during the period.

+ References

No definition available.

+ Details

Name:	usph_NumberOfClinicsConsolidatedWithExistingClinics
Namespace Prefix:	usph_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of clinics operated during the period.

+ References

No definition available.

+ Details

Name:	usph_NumberOfClinicsOperated
Namespace Prefix:	usph_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of clinics operates as a satellite clinic with existing partnerships during the period.

+ References

No definition available.

+ Details

Name:	usph_NumberOfClinicsOperatesAsASatelliteClinicWithExistingPartnerships
Namespace Prefix:	usph_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of regions of the entity operates.

+ References

No definition available.

+ Details

Name:	usph_NumberOfRegions
Namespace Prefix:	usph_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of third party facilities.

+ References

No definition available.

+ Details

Name:	usph_NumberOfThirdPartyFacilities
Namespace Prefix:	usph_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of combined business interest owned during the period.

+ References

No definition available.

+ Details

Name:	usph_PercentageOfCombinedBusinessInterestOwned
Namespace Prefix:	usph_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of general partnership interest owned during the period.

+ References

No definition available.

+ Details

Name:	usph_PercentageOfGeneralPartnershipInterestOwned
Namespace Prefix:	usph_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of limited partnership interest owned during the period.

+ References

No definition available.

+ Details

Name:	usph_PercentageOfLimitedPartnershipInterestOwned
Namespace Prefix:	usph_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Refers to the commencement period of redemption rights for redeemable non controlling interest.

+ References

No definition available.

+ Details

Name:	usph_RedeemableNonControllingInterestRedemptionRightsCommencementPeriod
Namespace Prefix:	usph_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_BusinessAcquisitionAxis=usph_MarchTwoThousandSeventeenAcquisitionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=usph_LeadingProviderOfIndustrialInjuryPreventionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TitleOfIndividualAxis=usph_EmployeeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TitleOfIndividualAxis=us-gaap_DirectorMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TitleOfIndividualAxis=us-gaap_OfficerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_FurnitureAndFixturesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_ComputerSoftwareIntangibleAssetMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_LeaseholdImprovementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Details)			3 Months Ended	6 Months Ended	12 Months Ended
	Apr. 30, 2018 Business	Feb. 28, 2018 Clinic	Jun. 30, 2018 USD ($) Clinic State Segment Region	Jun. 30, 2018 USD ($) Clinic State Facility	Dec. 31, 2017 USD ($) Clinic	Mar. 31, 2018 USD ($)	Mar. 23, 2017
Basis of Presentation [Abstract]
Percentage of general partnership interest owned				1.00%
Number of clinic practices acquired \| Clinic		2		2	2
Number of clinics consolidated with an existing clinic \| Clinic					1
Number of clinics that operate as a satellite clinic with existing partnerships \| Clinic					1
Number of clinics operated \| Clinic			581	581
Number of states where clinics are operated \| State			42	42
Number of third party facilities \| Facility				28
Mandatorily redeemable non-controlling interests \| $			$ 0	$ 0	$ 327,000	$ 327,000
Number of business segments \| Segment			1
Number of regions \| Region			6
Corporate income tax rate				21.00%
Unrecognized tax benefit \| $				$ 0
Accrued interest and penalties associated with any unrecognized tax benefits \| $			$ 0	0
Interest expense recognized \| $				$ 0
March 2017 Acquisition [Member]
Basis of Presentation [Abstract]
Percentage of interest acquired			55.00%	55.00%
Industrial Injury Prevention [Member]
Basis of Presentation [Abstract]
Percentage of interest acquired	65.00%						55.00%
Number of businesses merged \| Business	2
Percentage of combined business interest owned	59.45%
Employee [Member]
Deferred Compensation Arrangements [Abstract]
Period in which restrictions lapse on stock granted				4 years
Director [Member]
Deferred Compensation Arrangements [Abstract]
Period in which restrictions lapse on stock granted				1 year
Officer [Member]
Deferred Compensation Arrangements [Abstract]
Period in which restrictions lapse on stock granted				4 years
Minimum [Member]
Basis of Presentation [Abstract]
Percentage of limited partnership interest owned				49.00%
Redeemable non-controlling interest, redemption rights, commencement period				3 years
Minimum [Member] \| Furniture & Equipment [Member]
Basis of Presentation [Abstract]
Estimated useful lives				3 years
Minimum [Member] \| Software [Member]
Basis of Presentation [Abstract]
Estimated useful lives				3 years
Minimum [Member] \| Leasehold Improvements [Member]
Basis of Presentation [Abstract]
Estimated useful lives				3 years
Maximum [Member]
Basis of Presentation [Abstract]
Percentage of limited partnership interest owned				99.00%
Redeemable non-controlling interest, redemption rights, commencement period				5 years
Maximum [Member] \| Furniture & Equipment [Member]
Basis of Presentation [Abstract]
Estimated useful lives				8 years
Maximum [Member] \| Software [Member]
Basis of Presentation [Abstract]
Estimated useful lives				7 years
Maximum [Member] \| Leasehold Improvements [Member]
Basis of Presentation [Abstract]
Estimated useful lives				5 years