Stock-based Compensation - Equity Awards (Details) (2007 Stock Plan [Member]) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	20	3	69	493
Equity awards granted during the period, total, Grants in Period, Gross	116	7	333	536
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	91	4	92	7
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	5	0	172	36
Share-based Compensation Arrangement by Share-based Payment Award, Options, Semi-Annual Performance Period Multiplier, Maximum			2.75
Share-based Compensation Arrangement by Share-based Payment Award, Options, Performance Multiplier Maximum			2.5