Leases - Future Minimum Lease Rents (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Future Minimum Lease Rents Due [Abstract]
Asset cost of leased property	$ 89.0	$ 89.0
Carrying amount on leased property	58.8	60.0
Contingent rent expense on leases	2.7	2.6	$ 3.0
Minimum rent expense on leases	80.8	$ 73.0	$ 76.5
Direct Financing Lease, 2019	16.2
Direct Financing Lease, 2020	14.8
Direct Financing Lease, 2021	11.7
Direct Financing Lease, 2022	8.2
Direct Financing Lease, 2023	3.5
Thereafter	2.9
Total minimum rents receivable	57.3
Operating Lease, 2019	105.9
Operating Lease, 2020	106.3
Operating Lease, 2021	100.2
Operating Lease, 2022	96.2
Operating Lease, 2023	91.8
Thereafter	271.8
Total minimum rents receivable	$ 772.2