Final price paid per share for the purchase of the targeted number of shares, determined by an average market price over a fixed period of time.

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Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended	48 Months Ended	180 Months Ended
	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2021	Feb. 21, 2018
Accelerated Share Repurchases [Line Items]
Accelerated share repurchases, final price paid per share	$ 40.17		$ 19.94
Stock Repurchase Program, Authorized Amount				$ 50.0
Stock repurchased during period, shares	550,964		29,948,854
Stock Repurchased During Period, Value	$ 22.1
2018 Program [Member]
Accelerated Share Repurchases [Line Items]
Accelerated share repurchases, final price paid per share		$ 36.14
Stock repurchased during period, shares		5,300,535
Stock Repurchased During Period, Value		$ 191.5