Shareholders' Equity (Details) - USD ($)					1 Months Ended	9 Months Ended	12 Months Ended
	Aug. 10, 2015	Jul. 01, 2015	Jun. 24, 2015	Jan. 26, 2015	Sep. 30, 2014	Sep. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 11, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation costs included in consolidated net income (loss) (in dollars)							$ 7,870,000	$ 11,405,000	$ 11,746,000
Weighted Average Grant Date Fair Value
Common stock reserved for share-based awards outstanding and available future grants (in shares)							10,818,103
Stock repurchase program, authorized amount							$ 1,700,000.0			$ 10,000,000
Continuing operations
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation costs included in consolidated net income (loss) (in dollars)							7,870,000	11,405,000	11,746,000
Discontinued operations
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation costs included in consolidated net income (loss) (in dollars)							0	0	0
Maximum
Weighted Average Grant Date Fair Value
Total unrecognized compensation cost (in dollars)							3,200,000
Non-employee directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation costs included in consolidated net income (loss) (in dollars)							$ 499,000	$ 842,000	558,000
President
Number of Options
Granted (in shares)					815,217
Stock option
Weighted average assumptions used to value options granted and the grant date fair value
Expected life (in years)								4 years 5 months 1 day
Risk-free interest rate								1.43%
Expected volatility								52.00%
Dividend yield								0.00%
Fair value (usd per share)								$ 1.59
Number of Options
Outstanding at the beginning of the period (in shares)						3,740,000	3,740,000
Granted (in shares)							0
Exercised (in shares)							(1,554,000)
Expired or canceled (in shares)							(633,000)
Forfeited (in shares)							(2,000)
Outstanding at the end of the period (in shares)							1,551,000	3,740,000
Vested and expected to vest at the end of the period (in shares)							1,500,000
Exercisable at the end of the period (in shares)							1,042,000
Weighted Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)						$ 3.76	$ 3.76
Granted (in dollars per share)							0.00
Exercised (in dollars per share)							2.83
Expired or canceled (in dollars per share)							5.42
Forfeited (in dollars per share)							4.13
Outstanding at the end of the period (in dollars per share)							4.01	$ 3.76
Vested and expected to vest at the end of the period (in dollars per share)							4.02
Exercisable at the end of the period (in dollars per share)							$ 4.17
Weighted Average Remaining Contractual Term
Outstanding at the end of the period							4 years 3 months 18 days
Vested and expected to vest at the end of the period							4 years 3 months
Exercisable at the end of the period							3 years 7 months 10 days
Aggregate Intrinsic Value
Outstanding at the end of the period							$ 134,000
Vested and expected to vest at the end of period							134,000
Exercisable at the end of the period							134,000
Total intrinsic value of options exercised							$ 1,400,000	$ 1,200,000	500,000
Stock option | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual terms (years)							10 years
Stock option | President
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (years)					2 years 6 months
Options expiration period (years)					7 years
RSUs
Number of RSUs
Nonvested shares outstanding at the beginning of the period (in shares)						3,364,000	3,364,000
Granted (in shares)							2,895,000
Vested (in shares)							(1,441,000)
Forfeited (in shares)							(709,000)
Nonvested shares outstanding at the end of the period (in shares)							4,109,000	3,364,000
Weighted Average Grant Date Fair Value
Nonvested shares outstanding at the beginning of the period (in dollars per share)						$ 3.99	$ 3.99
Granted (in dollars per share)							3.47
Vested (in dollars per share)							3.94
Forfeited (in dollars per share)							4.07
Nonvested shares outstanding at the end of the period (in dollars per share)							$ 3.63	$ 3.99
Total fair value (in dollars)							$ 5,100,000	$ 9,700,000	$ 6,800,000
Total unrecognized compensation cost (in dollars)							$ 11,700,000
Weighted average period for recognition of unrecognized stock-based compensation expense							1 year 11 months 27 days
RSUs | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (years)							1 year
RSUs | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (years)							3 years
RSUs | Non-employee directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Value of common stock granted initial grant							$ 100,000
Value of common stock granted annual grant							$ 100,000
RSUs | Non-employee directors | Initial grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (years)							3 years
RSUs | Non-employee directors | Annual grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (years)							1 year
RSUs | President
Number of RSUs
Granted (in shares)					804,721
RSUs | Chief Administrative Officer
Number of RSUs
Granted (in shares)					150,000
PSUs
Number of RSUs
Granted (in shares)	5,000	47,550	69,558	79,761
Weighted Average Grant Date Fair Value
Granted (in dollars per share)							$ 4.16
Total unrecognized compensation cost (in dollars)							$ 2,200,000
Weighted average period for recognition of unrecognized stock-based compensation expense							2 years
PSUs | Common Class A
Weighted Average Grant Date Fair Value
Potential vesting common stock shares						605,605
2004 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock authorized for issuance							20,350,000
Number of share available for future grants							5,158,049
2004 Plan | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual terms (years)							2 years
2004 Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual terms (years)							3 years
2004 Plan | Stock option | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual terms (years)							4 years
2004 Plan | Stock option | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual terms (years)							10 years
Expiration term (years)							10 years
ESPP
Weighted Average Grant Date Fair Value
Contribution of compensation by the employees per calendar year, percentage							10.00%
Contribution of compensation by the employees per calendar year							$ 10,000
Percentage of the discount fair market value of common stock							95.00%
Offering period (months)							3 months
Number of shares issued (in shares)							215,000	184,000	206,000