Leases - Other information (Details) $ in Millions	6 Months Ended
	Jun. 30, 2019 USD ($)
Cash paid for amounts included in measurement of lease liabilities:
Operating cash flows from operating leases	$ 3.0
Financing cash flows from finance leases	1.7
Right-of-use assets obtained in exchange for lease obligations: Finance leases	9.3
Right-of-use assets obtained in exchange for lease obligations: Operating leases	$ 5.1