Earnings Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2019		Mar. 31, 2018	Dec. 31, 2018
Weighted Average Number of Shares Outstanding Basic and Diluted [Line Items]
Common Stock, Shares, Outstanding	102,466,571			107,785,559
Stock Repurchased and Retired During Period, Shares	1,260,163		800,000
Treasury Stock, Shares, Acquired	500,000		600,000
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Weighted-average number of common shares outstanding - basic	102,300,000		106,800,000
Weighted-average number of common shares outstanding - diluted	102,300,000	[1]	110,000,000
Potentially dilutive shares excluded from computation of dilutive earnings per share	5,800,000		2,800,000
Stock options
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Incremental Common Shares Attributable to Share-based Payment Arrangements	0		1,200,000
Restricted stock units
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Incremental Common Shares Attributable to Share-based Payment Arrangements	0		2,000,000

[1] (1) Due to the net loss during the three months ended March 31, 2019, the denominator in the diluted earnings per share calculation does not include the effects of the stock awards for which the average market price for the period exceeds the exercise price, as it would result in a less dilutive computation. As a result, reported diluted earnings per share for the three months ended March 31, 2019 are the same as basic earnings per share.