Face (par) amount of debt instrument at time of issuance.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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-Topic 835
-SubTopic 30
-Section 55
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-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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Balance Type:	credit
Period Type:	instant

- 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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Period Type:	duration

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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Balance Type:	debit
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

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Balance Type:	credit
Period Type:	duration

- Definition

Extension in period of time between issuance and maturity of debt instrument, 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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Balance Type:	na
Period Type:	duration

- Definition

Amount of debt issuance cost capitalized during the period.

+ References

No definition available.

+ Details

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

- Definition

The contingent increase above the maximum borrowing capacity under the credit facility, if any one or more of the existing banks or new banks agree to provide such increased commitment amount.

+ References

No definition available.

+ Details

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Namespace Prefix:	uthr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of line of credit paid during the period.

+ References

No definition available.

+ Details

Name:	uthr_LineOfCreditRepaidDuringPeriod
Namespace Prefix:	uthr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

It represents upfront payment for developing. manufacturing and commercialize ralinepag related to global license agreement.

+ References

No definition available.

+ Details

Name:	uthr_UpfrontPayment
Namespace Prefix:	uthr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_TypeOfArrangementAxis=uthr_ArenaPharmaceuticalsIncMember
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- Details

Name:	us-gaap_LongtermDebtTypeAxis=uthr_CreditAgreementMember
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Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=uthr_CreditAgreement2018FirstUnsecuredRevolvingCreditFacilityMember
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Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=uthr_CreditAgreement2018SecondUnsecuredRevolvingCreditFacilityMember
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Debt (Details) - USD ($) $ in Millions		1 Months Ended			3 Months Ended		9 Months Ended
Debt (Details) - USD ($) $ in Millions	Jan. 24, 2019	Jun. 30, 2019	Jan. 31, 2019	Jun. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jun. 27, 2018
Debt
Line of credit (current)					$ 250.0		$ 250.0
Debt issuance costs							0.7	$ 13.2
Arena Pharmaceuticals, Inc.
Debt
Upfront payment	$ 800.0		$ 800.0
Credit Agreement
Debt
Borrowing	800.0
Period of extension in maturity		1 year			1 year
Debt aggregate principal value									$ 250.0
Interest expense					$ 11.7	$ 4.1	34.2	9.6
Upfront payment	$ 800.0
Outstanding Balance					$ 1,000.0		1,000.0
Line of credit repaid during the period							$ 50.0
Debt issuance costs				$ 13.2
Debt issuance costs capitalized				12.6
First unsecured revolving credit facility
Debt
Borrowing						1,000.0		1,000.0
Second unsecured revolving credit facility
Debt
Borrowing						$ 500.0		$ 500.0
Increase in borrowing capacity				$ 300.0