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

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Stock-based Compensation (Details) - USD ($)			3 Months Ended		9 Months Ended
Stock-based Compensation (Details) - USD ($)	May 18, 2021	Jan. 31, 2019	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Stock-based compensation (benefit) expense			$ 1,200,000	$ 900,000	$ 6,300,000	$ 4,300,000
Income tax benefits related to the stock-based compensation plans			$ 300,000	200,000	$ 1,700,000	$ 1,000,000.0
Omnibus Plan 2014 [Member]
Number of shares authorized			1,171,343		1,171,343
Number of additional shares authorized	1,100,000
The 2019 Long-term Incentive Compensation Program [Member]
Awards vesting period		3 years
Restricted Stock Units (RSUs) [Member]
Awards granted					238,985	172,728
Restricted Stock Units (RSUs) [Member] \| Omnibus Plan 2014 [Member]
Total unrecognized compensation cost			$ 5,300,000		$ 5,300,000
Weighted-average period of recognition of compensation cost					2 years 4 months 24 days
Total fair value of awards vested			400,000	200,000	$ 5,400,000	$ 5,200,000
Performance-based Restricted Stock Units [Member]
Awards granted					62,790	72,143
Phantom Share Units (PSUs) [Member] \| Phantom Stock Plan [Member]
Stock-based compensation (benefit) expense			200,000	(100,000)	$ 800,000	$ (1,200,000)
Total fair value of awards vested			$ 24,000	$ 3,000	$ 50,000	$ 10,000