Share-Based Compensation and Capital Stock - Pre-Tax Stock-Based Compensation Expenses And Associated Income Tax Benefits (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-Based Compensation and Capital Stock [Line Items]
Total share-based compensation expense	$ 6,168	$ 3,378	$ 17,368	$ 2,891
Income tax expense	1,498	805	4,219	689
Stock options
Share-Based Compensation and Capital Stock [Line Items]
Total share-based compensation expense	933	497	2,482	1,478
Restricted stock awards
Share-Based Compensation and Capital Stock [Line Items]
Total share-based compensation expense	2,285	2,206	7,126	6,249
Performance vested restricted stock units
Share-Based Compensation and Capital Stock [Line Items]
Total share-based compensation expense	$ 2,950	$ 675	$ 7,760	$ (4,836)