Earnings (Loss) Per Share (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted Average Number of Shares Outstanding, Basic and Diluted	33,734	32,708	34,104
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	1,400	800	1,000
Weighted Average Number of Shares Outstanding, Diluted	33,734	32,708	34,104
Equity Option and Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	0	0	0
Equity Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	37	2,770	1,902