Earnings per Share (Details) - $ / shares	3 Months Ended												12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share, Basic and Diluted [Abstract]
Basic earnings per common share (in dollars per share)	$ 0.71	$ 0.67	$ 0.95	$ 0.84	$ 0.27	$ 0.93	$ 0.93	$ 0.83	$ 0.84	$ 0.77	$ 0.74	$ 0.83	$ 3.17	$ 2.97	$ 3.19
Diluted earnings per common share (in dollars per share)	$ 0.71	$ 0.67	$ 0.94	$ 0.84	$ 0.27	$ 0.92	$ 0.92	$ 0.83	$ 0.84	$ 0.76	$ 0.74	$ 0.83	$ 3.16	$ 2.95	$ 3.17
Basic weighted average shares outstanding (in shares)													30,511,000	31,393,000	31,552,000
Diluted weighted average shares outstanding (in shares)													30,594,000	31,534,000	31,719,000
Antidilutive securities excluded from computation (in shares)													181,875	42,000	0
Weighted Average Number of Shares Outstanding, Diluted [Abstract]
Basic weighted average shares outstanding (in shares)													30,511,000	31,393,000	31,552,000
Incremental shares for common stock equivalents (in shares)													83,000	141,000	167,000
Diluted shares outstanding (in shares)													30,594,000	31,534,000	31,719,000