Earnings Per Share Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Diluted earnings per share - Numerator:
Net income from continuing operations attributable to common shareholders, after assumed dilution	$ 20,999	$ 20,965
Net Income (Loss) from Continuing Operations Available to Common Stockholders, Diluted	20,999	20,965
Net income from discontinued operations	0	1,698
Net income attributable to common shareholders, after assumed dilution	$ 20,999	$ 22,663
Diluted earnings per share - Denominator:
Weighted average basic common shares outstanding (in shares)	83,285,095	83,097,758
Dilutive effect of:
Time-based and market-based stock options, performance-based and time-based restricted stock, and performance-based and time-based restricted stock units, and other dilutive securities (in shares)	725,355	1,136,145
Warrants to purchase common stock (in shares)	0	1,037,747
Dilutive common shares (in shares)	725,355	2,173,892
Weighted average diluted common shares outstanding (in shares)	84,010,450	85,271,650
Per share data - Diluted earnings per share from:
Continuing operations (in dollars per share)	$ 0.25	$ 0.25
Discontinued operations (in dollars per share)	0	0.02
Total attributable to common shareholders (in dollars per share)	0.25	0.27
Dividends per share declared and paid on common stock (in dollars per share)	$ 0.12	$ 0.12