Earnings per Share Repurchase of Common Stock (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2015
Stock Repurchased and Retired During Period, Value	$ 31,570	$ 670
10b5-1 share repurchase program [Member]
Stock Repurchase Program, Authorized Amount	$ 250,000		$ 50,000
Stock Repurchased and Retired During Period, Shares	1,253,650	24,900
Stock Repurchased and Retired During Period, Value	$ 31,600	$ 700

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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