Shareholders' Equity (Details) - USD ($) shares in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	May 31, 2019
Class of Stock [Line Items]
Dividends	$ 32,447,000	$ 30,633,000	$ 65,056,000	$ 61,463,000
Payments for repurchase of common stock			$ 95,676,000	$ 108,471,000
Increase in share repurchase authorization					$ 500,000,000.0
Share repurchase plan
Class of Stock [Line Items]
Share repurchases (shares)			2.8	3.5
Payments for repurchase of common stock			$ 95,700,000	$ 108,500,000
Remaining value of stock repurchase programs authorization	$ 429,900,000		429,900,000
Shares withheld to pay taxes
Class of Stock [Line Items]
Payments for repurchase of common stock			$ 14,900,000	$ 10,400,000