Fair Value Measurements (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Assets:
Cash and cash equivalents	$ 20.3	$ 16.2
Interest rate swaps	6.7	6.7
Liabilities:
Interest rate swaps	4.5	0.0
Level 1
Assets:
Cash and cash equivalents	20.3	16.2
Interest rate swaps	0.0	0.0
Liabilities:
Interest rate swaps	0.0	0.0
Level 2
Assets:
Cash and cash equivalents	0.0	0.0
Interest rate swaps	6.7	6.7
Liabilities:
Interest rate swaps	4.5	0.0
Level 3
Assets:
Cash and cash equivalents	0.0	0.0
Interest rate swaps	0.0	0.0
Liabilities:
Interest rate swaps	$ 0.0	$ 0.0