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Earnings Per Common Share - Textual (Details) - USD ($)	1 Months Ended				12 Months Ended
Earnings Per Common Share - Textual (Details) - USD ($)	Oct. 31, 2019	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jul. 24, 2018	Feb. 01, 2014	Jan. 31, 2014
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Antidilutive shares excluded from computation of diluted weighted-average shares (in shares)					200,000	100,000	0
Common stock repurchased					$ 6,100,000	$ 45,900,000
Cash dividends declared per common share (in dollars per share)					$ 1.12	$ 1.10	$ 1.04
Common Stock
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Common stock repurchase authorization								$ 250,000,000	$ 250,000,000	$ 200,000,000
Common stock repurchased (in shares)					100,000	800,000	0
Common stock repurchased					$ 6,100,000	$ 45,900,000
Cash dividends declared per common share (in dollars per share)		$ 0.28	$ 0.27	$ 0.25
Cash dividends paid per common share (in dollars per share)	$ 0.28		$ 0.27	$ 0.25