Commitments and Contingencies (Details) (USD $)	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013	Dec. 31, 2013
Contractual obligations
Contractual Obligation	$ 390,159,000	[1]
Remainder of 2014	203,535,000	[1]
2015	12,616,000	[1]
2016	9,325,000	[1]
2017	8,873,000	[1]
2018	146,339,000	[1]
Thereafter	9,471,000	[1]
Unrecognized tax benefits	20,000,000			18,800,000
Unrecognized tax benefits, reduction of long-term deferred tax assets	18,000,000			12,600,000
Unrecognized tax benefits included in long-term income taxes payable	2,000,000			6,200,000
Terms of noncancellable license agreement, minimum (in years)	1 year
Remaining CRI retention bonuses payable	16,700,000
Rent expense	600,000		900,000
Deferred rent	1,300,000			1,400,000
Imputed financing obligation
Contractual obligations
Contractual Obligation	38,808,000	[1],[2]
Remainder of 2014	4,422,000	[1],[2]
2015	6,010,000	[1],[2]
2016	6,156,000	[1],[2]
2017	6,302,000	[1],[2]
2018	6,447,000	[1],[2]
Thereafter	9,471,000	[1],[2]
Leases and other contractual obligations
Contractual obligations
Contractual Obligation	7,118,000	[1]
Remainder of 2014	2,399,000	[1]
2015	2,118,000	[1]
2016	1,243,000	[1]
2017	1,018,000	[1]
2018	340,000	[1]
Thereafter	0	[1]
Software licenses
Contractual obligations
Contractual Obligation	5,684,000	[1],[3]
Remainder of 2014	2,446,000	[1],[3]
2015	2,865,000	[1],[3]
2016	373,000	[1],[3]
2017	0	[1],[3]
2018	0	[1],[3]
Thereafter	0	[1],[3]
Acquisition retention bonuses
Contractual obligations
Contractual Obligation	16,749,000	[1],[4]
Remainder of 2014	16,679,000	[1],[4]
2015	70,000	[1],[4]
2016	0	[1],[4]
2017	0	[1],[4]
2018	0	[1],[4]
Thereafter	0	[1],[4]
Convertible notes
Contractual obligations
Contractual Obligation	310,500,000	[1]
Remainder of 2014	172,500,000	[1]
2015	0	[1]
2016	0	[1]
2017	0	[1]
2018	138,000,000	[1]
Thereafter	0	[1]
Interest payments related to convertible notes
Contractual obligations
Contractual Obligation	11,300,000	[1]
Remainder of 2014	5,089,000	[1]
2015	1,553,000	[1]
2016	1,553,000	[1]
2017	1,553,000	[1]
2018	1,552,000	[1]
Thereafter	$ 0	[1]

[1] The above table does not reflect possible payments in connection with uncertain tax benefits of approximately $20.0 million including $18.0 million recorded as a reduction of long-term deferred tax assets and $2.0 million in long-term income taxes payable as of March 31, 2014. As noted below in Note 13, “Income Taxes,” although it is possible that some of the unrecognized tax benefits could be settled within the next 12 months, the Company cannot reasonably estimate the outcome at this time.

[2] With respect to the imputed financing obligation, the main components of the difference between the amount reflected in the contractual obligations table and the amount reflected on the condensed consolidated balance sheets are the interest on the imputed financing obligation and the estimated common area expenses over the future periods. Additionally, the amount includes the amended Ohio lease and the amended Sunnyvale lease.

[3] The Company has commitments with various software vendors for non-cancellable license agreements generally having terms longer than one year. The above table summarizes those contractual obligations as of March 31, 2014 which are also presented on the Company’s condensed consolidated balance sheet under current and other long-term liabilities.

[4] In connection with acquisitions, the Company is obligated to pay retention bonuses to certain employees and contractors, subject to certain eligibility and acceleration provisions including the condition of employment. The remaining $16.7 million of CRI retention bonuses payable on June 3, 2014 can be paid in cash or stock at the Company’s election.