Selected Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Quarterly Financial Data [Abstract]
Net revenues	$ 117,349	$ 113,122	$ 115,098	$ 108,342	$ 109,203	$ 103,032	$ 104,251	$ 97,565	$ 453,911	$ 414,051	$ 356,546
Operating income	14,804	15,433	17,026	13,051	13,962	12,888	15,678	12,200	$ 60,314	$ 54,728	$ 49,533
Net income	13,673	11,879	13,236	10,054	8,706	6,594	6,390	6,034
Net income attributable to USPH shareholders	$ 10,408	$ 8,102	$ 9,246	$ 7,117	$ 7,349	$ 5,150	$ 4,941	$ 4,816
Basic and diluted earnings per share attributable to common shareholders (in dollars per share)	$ 0.43	$ 0.13	$ 0.48	$ 0.27	$ 0.57	$ 0.41	$ 0.39	$ 0.38	$ 1.31	$ 1.76	$ 1.64
Shares used in computation - basic and diluted (in shares)	12,685	12,685	12,677	12,616	12,593	12,581	12,579	12,528	12,666	12,570	12,500
Net Patient Revenues [Member]
Quarterly Financial Data [Abstract]
Net revenues	$ 107,808	$ 103,354	$ 105,989	$ 100,552	$ 101,642	$ 96,273	$ 97,657	$ 93,654	$ 417,703	$ 389,226	$ 348,839

The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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