Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

No definition available.

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- Definition

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

+ References

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

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- Definition

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- 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://fasb.org/us-gaap/role/ref/legacyRef
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-Section 30
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

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- Definition

Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1
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Period Type:	instant

- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Period Type:	instant

- Definition

Amount of assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

+ References

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Data Type:	num:percentItemType
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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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Period Type:	duration

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
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-SubTopic 10
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Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

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Balance Type:	credit
Period Type:	duration

- Definition

The amount of business acquisition cost of acquired entity debt issued on the date of acquisition.

+ References

No definition available.

+ Details

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

- Definition

Business acquisition number of installments for payment of purchase consideration.

+ References

No definition available.

+ Details

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

- Definition

The amount payable to shareholders of seller in business acquisition.

+ References

No definition available.

+ Details

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

- Definition

Amount of business acquisition principal installments payable at cost of acquired by entity at accrued interest.

+ References

No definition available.

+ Details

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

- Definition

Amount of net tangible asset acquired at the acquisition date.

+ References

No definition available.

+ Details

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Namespace Prefix:	usph_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Useful life of acquired finite-lived intangible assets in business combination, 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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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the fair value of the redeemable noncontrolling interest in the acquiree at the acquisition date.

+ References

No definition available.

+ Details

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

- Definition

The amount of non-competition agreements recognized as of the acquisition date.

+ References

No definition available.

+ Details

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Namespace Prefix:	usph_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of referral relationships at the acquisition date.

+ References

No definition available.

+ Details

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Namespace Prefix:	usph_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of tradename recognized as of the acquisition date.

+ References

No definition available.

+ Details

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Namespace Prefix:	usph_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

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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 client locations that included in total operated states that are providing industrial injury prevention services.

+ References

No definition available.

+ Details

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

- Definition

This element represents number of states of network services provided by the company.

+ References

No definition available.

+ Details

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

- Definition

Payments to acquire businesses total consideration.

+ References

No definition available.

+ Details

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Namespace Prefix:	usph_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of combined business interest owned during the period.

+ References

No definition available.

+ Details

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

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_NoncompeteAgreementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

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Balance Type:
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- Details

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- Details

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Namespace Prefix:
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Balance Type:
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- Details

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Period Type:

- Details

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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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

- Details

Name:	us-gaap_BusinessAcquisitionAxis=usph_AcquisitionOfFiveClinicPracticesMember
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ACQUISITIONS OF BUSINESSES (Details) $ in Thousands						1 Months Ended	9 Months Ended		12 Months Ended
ACQUISITIONS OF BUSINESSES (Details) $ in Thousands	Sep. 30, 2019 USD ($) Installment Clinic	Apr. 11, 2019 USD ($) State Location	Aug. 31, 2018 USD ($) Installment Clinic	Apr. 30, 2018 USD ($) Business	Feb. 28, 2018 Clinic	Mar. 31, 2017 USD ($)	Sep. 30, 2019 USD ($) Installment	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($) Clinic
Business Combination, Description [Abstract]
Number of clinics \| Clinic			4		2				5
Cash paid for acquisition of interest in clinic							$ 5,700
Business acquisition number of installments for payment of purchase consideration \| Installment							2
Cash paid, net of cash acquired				$ 16,367			$ 30,365	$ 16,303
Seller notes	$ 283			950			$ 283	$ 0
Total consideration				17,317
Estimated fair value of net tangible assets acquired [Abstract]
Total current assets				1,633
Total non-current assets				305
Total liabilities				(525)
Net tangible assets acquired				1,413
Referral relationships				2,926
Non-compete				298
Tradename				990
Goodwill				19,835
Fair value of non-controlling interest (classified as redeemable non-controlling interests)				(8,145)
Total consideration				$ 17,317
Referral Relationships [Member]
Estimated fair value of net tangible assets acquired [Abstract]
Estimated useful lives of acquired intangibles							11 years		10 years 6 months 14 days
Non-compete Agreements [Member]
Estimated fair value of net tangible assets acquired [Abstract]
Estimated useful lives of acquired intangibles							6 years		6 years
April 2019 Acquisition [Member]
Business Combination, Description [Abstract]
Acquisition date							Apr. 11, 2019
Number of states of network services \| State		45
Number of onsite client locations \| Location		11
Percentage of interest acquired		76.00%
Aggregate purchase price for the acquired clinic practices		$ 23,600
Cash paid for acquisition of interest in clinic		$ 19,600
Percentage of interest accrued		5.50%
Cash paid, net of cash acquired		$ 30,365
Payable to shareholders of seller	$ 500	502					$ 500
Seller notes		4,000
Total consideration		35,167
Estimated fair value of net tangible assets acquired [Abstract]
Total current assets		2,824
Total non-current assets		2,924
Total liabilities		(3,034)
Net tangible assets acquired		2,714
Referral relationships		3,000
Non-compete		1,290
Tradename		4,100
Goodwill		30,293
Fair value of non-controlling interest (classified as redeemable non-controlling interests)		(6,230)
Total consideration		$ 35,167
September 2019 Acquisition [Member]
Business Combination, Description [Abstract]
Acquisition date							Sep. 30, 2019
Percentage of interest acquired	67.00%						67.00%
Number of clinics \| Clinic	11
Aggregate purchase price for the acquired clinic practices	$ 12,400
Cash paid for acquisition of interest in clinic	$ 12,100
Business acquisition number of installments for payment of purchase consideration \| Installment	2
Percentage of interest accrued	5.00%						5.00%
Seller notes	$ 300						$ 300
September 2019 Acquisition [Member] \| September 2020 [Member]
Business Combination, Description [Abstract]
Acquisition cost payable in two principal installments including accrued interest	150
September 2019 Acquisition [Member] \| September 2021 [Member]
Business Combination, Description [Abstract]
Acquisition cost payable in two principal installments including accrued interest	$ 150
August 2018 Acquisition [Member]
Business Combination, Description [Abstract]
Acquisition date							Aug. 31, 2018
Percentage of interest acquired			70.00%
Number of clinics \| Clinic			4
Cash paid for acquisition of interest in clinic			$ 7,300
Business acquisition number of installments for payment of purchase consideration \| Installment			2
Seller notes			$ 400
August 2018 Acquisition [Member] \| August 2019 [Member]
Business Combination, Description [Abstract]
Cash paid for acquisition of interest in clinic			200
August 2018 Acquisition [Member] \| August 2020 [Member]
Business Combination, Description [Abstract]
Acquisition cost payable in two principal installments including accrued interest			$ 200
Industrial Injury Prevention [Member]
Business Combination, Description [Abstract]
Percentage of interest acquired				65.00%		55.00%
Cash paid for acquisition of interest in clinic				$ 8,600		$ 6,200
Number of businesses merged \| Business				2
Percentage of combined business interest owned				59.45%
Seller notes				$ 400		$ 400
Acquisition of Five Clinic Practices [Member]
Business Combination, Description [Abstract]
Number of clinics \| Clinic									5
Aggregate purchase price for the acquired clinic practices									$ 1,000
Cash paid for acquisition of interest in clinic									850
Seller notes									$ 150
Acquisition of Five Clinic Practices [Member] \| August 2019 [Member]
Business Combination, Description [Abstract]
Percentage of interest accrued									4.50%