Shareholders' Equity - Narrative (Details) - USD ($) $ / shares in Units, shares in Millions	1 Months Ended		3 Months Ended						9 Months Ended		25 Months Ended
	Oct. 31, 2020	Feb. 29, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Oct. 31, 2020	Oct. 31, 2018
Subsequent Event
Dividends paid									$ (16,200,000)	$ (15,700,000)
Cash dividends per share, declared (in dollars per share)			$ 0.26	$ 0.26	$ 0.26	$ 0.25	$ 0.25	$ 0.25
Repurchase of common stock									$ 5,300,000	$ 15,000,000.0
Employee Stock Options
Subsequent Event
Option term		10 years
Average expected term									6 years
Fair value (in dollars per share)									$ 13.64
Common Stock
Subsequent Event
Shares repurchases (in shares)									0.1
Common Stock | Employee Stock Options
Subsequent Event
Options issued (in shares)		0.1
Exercise price (in dollars per share)		$ 53.78
Share Repurchase Plan
Subsequent Event
Stock repurchase program, authorized amount (up to)												$ 50,000,000.0
Repurchase of common stock									$ 5,300,000
Subsequent Event
Subsequent Event
Cash dividends per share, declared (in dollars per share)	$ 0.26
Subsequent Event | Common Stock
Subsequent Event
Shares repurchases (in shares)											0.3
Subsequent Event | Share Repurchase Plan
Subsequent Event
Stock repurchase program, authorized amount (up to)	$ 50,000,000										$ 50,000,000
Repurchase of common stock											$ 20,300,000