Leases - Schedule of Future Minimum Annual Payments for Ground Leases (Details) - Ground - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Operating Lease, After Adopting 842
2019	$ 0.6
2020	1.2
2021	1.2
2022	1.2
2023	1.3
Thereafter	388.1
Total	$ 393.6
Operating Lease, Annual Payments, Before Adopting 842
2019		$ 1.2
2020		1.2
2021		1.2
2022		1.3
2023		1.3
Thereafter		388.0
Total		$ 394.2

Amount of lessee's undiscounted obligation for lease payments for operating lease.

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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