Accounting Policies - Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended
		Mar. 31, 2016	Mar. 31, 2015
Accounting Policies [Abstract]
Net income attributable to common stockholders (Dilutive)		$ 10,317	$ 1,818
Stock options, SARs and restricted stock	[1]	538	393
Earnings Per Share, On Incremental Common Shares Attributable to Share-based Payment Arrangements	[1]	$ (0.05)	$ (0.01)
Weighted Average Number of Shares Outstanding, Diluted		11,003	11,331
Diluted earnings per common share		$ 0.94000	$ 0.16000
Earnings Per Share, Basic [Abstract]
Net Income (Loss) Available to Common Stockholders, Basic		$ 10,317	$ 1,818
Weighted Average Number of Shares Outstanding, Basic		10,465	10,938
Basic earnings per common share		$ 0.99	$ 0.17

[1] For the three months ended March 31, 2016 and 2015, stock options and SARs of 210,865 and 201,401, respectively, were outstanding but not included in the computation of diluted earnings per share of common stock because they were anti-dilutive. For the three months ended March 31, 2016 and 2015, contingent shares of non-vested restricted stock of 37,284 and 30,514, respectively, were outstanding but not included in the computation of diluted earnings per share of common stock because performance conditions had not yet been met.