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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Period Type:	duration

Stockholders' Equity - Common Stock (Details) - Share Repurchase Program - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Feb. 29, 2020	Feb. 28, 2017
Stockholders' equity
Repurchase Program, remaining authorized capacity	$ 400.0
Maximum
Stockholders' equity
Stock Repurchase Program, maximum amount authorized for repurchase		$ 500.0	$ 300.0
Common Stock
Stockholders' equity
Repurchase Program, number of shares repurchased (in shares)	9,770,081
Repurchase Program, value of shares repurchased	$ 103.9
Preferred Stock
Stockholders' equity
Repurchase Program, number of shares repurchased (in shares)	0