Deferred Revenue - Schedule of deferred revenue (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Current portion:
Deferred revenue, current	$ 452.5	$ 320.1
Long-term portion:
Deferred revenue, noncurrent	464.2	629.2
Sanofi
Current portion:
Deferred revenue, current	246.7	177.7
Long-term portion:
Deferred revenue, noncurrent	279.3	379.9
Bayer
Current portion:
Deferred revenue, current	44.4	39.0
Long-term portion:
Deferred revenue, noncurrent	45.1	29.7
Teva
Current portion:
Deferred revenue, current	92.5	43.5
Long-term portion:
Deferred revenue, noncurrent	102.0	153.9
Other
Current portion:
Deferred revenue, current	68.9	59.9
Long-term portion:
Deferred revenue, noncurrent	$ 37.8	$ 65.7