Revenue - Revenue from Licensing Arrangements (Details) - Mylan - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Jan. 31, 2015
Collaborative Arrangements and Co-Promote Agreement
Potential milestone or contingent payments		$ 205.0
Upfront payment receivable	$ 18.5
YUPELRI Monotherapy
Collaborative Arrangements and Co-Promote Agreement
Potential milestone or contingent payments	9.0	160.0
YUPELRI Monotherapy | Sales milestones
Collaborative Arrangements and Co-Promote Agreement
Potential milestone or contingent payments	37.5	150.0
YUPELRI Monotherapy | European Union Regulatory Issues [Member]
Collaborative Arrangements and Co-Promote Agreement
Potential milestone or contingent payments		10.0
Future potential combination products
Collaborative Arrangements and Co-Promote Agreement
Potential milestone or contingent payments	7.5	$ 45.0
Future potential combination products | Development and Sales Milestones
Collaborative Arrangements and Co-Promote Agreement
Potential milestone or contingent payments	$ 54.0