Earnings Per Share - Reconciliation of Number of Common Stock used in Computing Basic and Diluted Earning Per Share (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Weighted Average Number Of Shares Outstanding [Abstract]
Weighted average shares outstanding - basic	117,188,398	119,820,422	117,946,805	120,711,513
Dilutive effect of share-based awards	745,042	163,731	750,031	171,323
Weighted average shares outstanding - diluted	117,933,440	119,984,153	118,696,836	120,882,836