Agreements and Transactions with Baxter (Amounts Due From and To Baxter) (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Related Party Transactions [Abstract]
Accounts receivable from Baxter	$ 104.4	$ 103.1
Accounts payable to Baxter (current)	33.8	63.2
Accounts payable to Baxter (non-current)	$ 59.6	$ 59.6