Summary of Significant Accounting Policies (Details 4) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Revenue Recognition [Abstract]
Shelf life of Remodulin, Tyvaso and Orenitram sold to customers, minimum	1 year
Inventory holding period of Remodulin,Tyvaso and Orenitram, low end of range	30 days
Inventory holding period of Remodulin, Tyvaso and Orenitram, high end of range	60 days
Maximum exchanges of Remodulin, Tyvaso and Orenitram as compared to the total volume of units sold (as a percent)	1.00%
Reduction in allowance for returns associated with goods due to change in the methodology for estimating returns		$ 3.1
Income taxes
Minimum percentage of likelihood of realization of recognized tax benefit	50.00%

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Represents the reduction of allowance for returns associated with goods due to revision in the methodology for estimating returns.

No definition available.

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Represents the high end of the range of the inventory holding period.

No definition available.

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Represents the low end of the range of the inventory holding period.

No definition available.

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Represents the minimum percentage of likelihood of realization of recognized benefit.

No definition available.

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Represents the maximum percentage of exchanges of Remodulin and Tyvaso as compared to the total volume of units sold.

No definition available.

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Represents the minimum shelf life of a product.

No definition available.

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