Basic and Diluted Net Income (Loss) Per Share - Anti-Dilutive Securities (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Contingently Issuable Shares [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount			0	1,300,000
Convertible Debt Securities [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount			2,400,000	3,500,000
Stock Compensation Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	4,903,000	3,458,000	4,900,000	3,726,000
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	2,375,000	2,330,000	2,375,000	2,400,000
Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	441,000	399,000	438,000	478,000
Securities Excluded from Computation of Earnings Per Share, Performance Target Not Met, Amount	2,087,000	729,000	2,087,000	848,000
Long-term Incentive Plan [Member] | Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities Excluded from Computation of Earnings Per Share, Performance Target Not Met, Amount	2,000,000
Overlay Plan [Member] | Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities Excluded from Computation of Earnings Per Share, Performance Target Met, Amount	100,000