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, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested, ending balance (in shares)	1,652,970		1,652,970
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)	260,000		260,000
Share-based compensation recognized cost			$ 0.1
Service-Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested, ending balance (in shares)	1,392,970		1,392,970
Share-based compensation recognized cost	$ 0.8	$ 0.6	$ 1.4	$ 1.2
Unrecognized amount	$ 7.6		$ 7.6
Unrecognized cost, period for recognition			3 years