Summary of Significant Accounting Policies - Supplemental Balance Sheet Information (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Operating Leases
Operating lease right-of-use assets	$ 134.5
Other accrued liabilities	66.8
Long-term operating lease liabilities	96.1
Total operating lease liabilities	162.9
Finance Leases
Outsourcing assets, net	4.7
Current maturities of long-term debt	1.6
Long-term debt	3.8
Total finance lease liabilities	$ 5.4	$ 5.8
Weighted-Average Remaining Lease Term
Operating leases	3 years 3 months 18 days
Finance leases	3 years 2 months 12 days
Weighted-Average Discount Rate
Operating leases	6.30%
Finance leases	2.60%