Share Repurchase Plan (Details) - USD ($)	1 Months Ended	3 Months Ended	9 Months Ended	17 Months Ended
	Oct. 30, 2019	Sep. 30, 2019	Sep. 30, 2019	Aug. 31, 2019	Sep. 16, 2019	Mar. 19, 2018
Equity, Class of Treasury Stock [Line Items]
Cost to repurchase common shares		$ 3,100,000	$ 18,222,000
March 19, 2018 Plan
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount						$ 50,000,000
Repurchased common shares (in shares)		84,868	470,708	792,439
Cost to repurchase common shares		$ 3,100,000	$ 18,200,000	$ 30,500,000
Cost to repurchase common shares (in dollars per share)		$ 36.52	$ 38.71	$ 38.46
September 16, 2019 Plan
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount					$ 50,000,000
Subsequent Event | September 16, 2019 Plan
Equity, Class of Treasury Stock [Line Items]
Repurchased common shares (in shares)	0