Stock-Based Compensation (Details) (USD $)	0 Months Ended	3 Months Ended		9 Months Ended				1 Months Ended	3 Months Ended	5 Months Ended	12 Months Ended
	Jun. 02, 2014	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014 RSAs Performance-contingent	Sep. 30, 2014 2012 Equity Incentive Plan	May 31, 2014 Special Long-Term Retention and Incentive Awards Program RSAs Performance-contingent	Mar. 31, 2014 Special Long-Term Retention and Incentive Awards Program RSAs Performance-contingent	May 31, 2014 Special Long-Term Retention and Incentive Awards Program RSAs Performance-contingent	Dec. 31, 2011 Special Long-Term Retention and Incentive Awards Program RSAs Performance-contingent	Sep. 30, 2014 Special Long-Term Retention and Incentive Awards Program RSAs Performance-contingent
Stock-based compensation
Shares remaining available for issuance							2,961,225
Period for which compensation committee has approved grants						3 years
Shares of common stock approved and authorized for issuance											1,290,000
Timeframe for achievement of performance conditions											6 years
Stock-based compensation expense		$ 4,732,000	$ 6,446,000	$ 26,013,000	$ 19,704,000				$ 6,800,000
Total stock-based compensation that will be recognized in the year										7,000,000
RSAs outstanding (in shares)												63,000
Number of shares of Theravance Biopharma issued for every share of Theravance	0.286
Stock-based compensation expenses expected to be recognized								$ 3,800,000
Vesting period								12 months