Common Stock Stock Repurchase (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Apr. 30, 2019
Equity, Class of Treasury Stock [Line Items]
Document Period End Date				Jun. 30, 2020
Stock Repurchase Program, Authorized Amount	$ 525,000			$ 525,000		$ 200,000
Payments for Repurchase of Common Stock				8,180	$ 3,717
Treasury Stock, Common [Member]
Equity, Class of Treasury Stock [Line Items]
Stock Repurchased During Period, Shares	(1,300,000)	(1,266,000)	(3,136,406)
Payments for Repurchase of Common Stock	$ 23,800
Treasury Stock remaining to be repurchased				$ 346,800