Earnings Per Share - Reconciliation of Shares Used in Calculating Earnings Per Basic and Diluted Shares (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Earnings Per Share [Abstract]
Weighted average common shares outstanding—basic (in shares)	25,742	25,885	25,646	25,978
Dilutive effect of stock-based awards (in shares)	132	196	225	283
Dilutive effect of convertible senior notes (in shares)	0	838	0	856
Weighted average common shares outstanding—diluted (in shares)	25,874	26,919	25,871	27,117