Earnings Per Share (Details) - shares	3 Months Ended			9 Months Ended
	Sep. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Class of Stock [Line Items]
Weighted average common shares outstanding for basic calculation (shares)	267,265,705		290,112,233	267,908,427	290,410,859
Add: Effect of stock options, deferred stock units and restricted stock units (shares)	13,850		15,063	12,463	11,492
Weighted average common shares outstanding for diluted calculation (shares)	267,279,555		290,127,296	267,920,890	290,422,351
Participating securities (shares)	77,157		36,546	65,264	28,914
Anti-dilutive shares (shares)	1,730,960		1,303,854	1,644,002	1,203,220
Common Stock
Class of Stock [Line Items]
Stock Repurchased and Retired During Period, Shares		3,328,574	879,134	3,328,574	0