Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Share-based Compensation - Omnibus Plan Other Information (Details) - The 2018 Omnibus Incentive Plan [Member] - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested, ending balance (in shares)	818,273		818,273
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			1 year
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			5 years
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested, ending balance (in shares)	175,000		175,000
Unrecognized amount	$ 1.3		$ 1.3
Service-Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested, ending balance (in shares)	643,273		643,273
Share-based compensation recognized cost	$ 0.6	$ 0.0	$ 1.2	$ 0.0
Unrecognized amount	$ 5.5		$ 5.5
Unrecognized cost, period for recognition			3 years 8 months 12 days