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.

No definition available.

+ Details

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

- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Net number of share options (or share units) granted during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shareholder-approved equity incentive plans.

+ References

No definition available.

+ Details

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

- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Share-Based Compensation - General (Details)	1 Months Ended	3 Months Ended
Share-Based Compensation - General (Details)	Feb. 28, 2019 shares	Mar. 31, 2019 item shares
Share-Based Compensation
Number of equity incentive plans \| item		2
2015 Plan
Share-Based Compensation
Maximum number of shares authorized to be issued		9,050,000
2019 Inducement Plan \| Newly-hired employees
Share-Based Compensation
Granted (in shares)	99,000
Amended and Restated Equity Incentive Plan (The 1999 Plan)
Share-Based Compensation
Granted (in shares)		0