Commitments and Contingencies (Details) (USD $)	3 Months Ended			6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013	Jun. 30, 2014		Jun. 30, 2013	Dec. 31, 2013
Contractual obligations
Remainder of 2014	$ 11,332,000	[1]		$ 11,332,000	[1]
2015	15,500,000	[1]		15,500,000	[1]
2016	10,700,000	[1]		10,700,000	[1]
2017	8,873,000	[1]		8,873,000	[1]
2018	146,339,000	[1]		146,339,000	[1]
Thereafter	9,471,000	[1]		9,471,000	[1]
Contractual Obligation	202,215,000	[1]		202,215,000	[1]
Unrecognized tax benefits	19,800,000			19,800,000			18,800,000
Unrecognized tax benefits, reduction of long-term deferred tax assets	17,900,000			17,900,000			12,600,000
Unrecognized tax benefits included in long-term income taxes payable	1,900,000			1,900,000			6,200,000
Terms of noncancellable license agreement, minimum (in years)				1 year
Remaining CRI retention bonuses payable	1,500,000			1,500,000
Rent expense	700,000		900,000	1,300,000		1,800,000
Deferred rent	1,300,000			1,300,000			1,400,000
Imputed financing obligation
Contractual obligations
Remainder of 2014	2,970,000	[1],[2]		2,970,000	[1],[2]
2015	6,011,000	[1],[2]		6,011,000	[1],[2]
2016	6,156,000	[1],[2]		6,156,000	[1],[2]
2017	6,302,000	[1],[2]		6,302,000	[1],[2]
2018	6,447,000	[1],[2]		6,447,000	[1],[2]
Thereafter	9,471,000	[1],[2]		9,471,000	[1],[2]
Contractual Obligation	37,357,000	[1],[2]		37,357,000	[1],[2]
Leases and other contractual obligations
Contractual obligations
Remainder of 2014	2,449,000	[1]		2,449,000	[1]
2015	2,250,000	[1]		2,250,000	[1]
2016	1,243,000	[1]		1,243,000	[1]
2017	1,018,000	[1]		1,018,000	[1]
2018	340,000	[1]		340,000	[1]
Thereafter	0	[1]		0	[1]
Contractual Obligation	7,300,000	[1]		7,300,000	[1]
Software licenses
Contractual obligations
Remainder of 2014	3,657,000	[1],[3]		3,657,000	[1],[3]
2015	5,616,000	[1],[3]		5,616,000	[1],[3]
2016	1,748,000	[1],[3]		1,748,000	[1],[3]
2017	0	[1],[3]		0	[1],[3]
2018	0	[1],[3]		0	[1],[3]
Thereafter	0	[1],[3]		0	[1],[3]
Contractual Obligation	11,021,000	[1],[3]		11,021,000	[1],[3]
Acquisition retention bonuses
Contractual obligations
Remainder of 2014	1,480,000	[1],[4]		1,480,000	[1],[4]
2015	70,000	[1],[4]		70,000	[1],[4]
2016	0	[1],[4]		0	[1],[4]
2017	0	[1],[4]		0	[1],[4]
2018	0	[1],[4]		0	[1],[4]
Thereafter	0	[1],[4]		0	[1],[4]
Contractual Obligation	1,550,000	[1],[4]		1,550,000	[1],[4]
Convertible notes
Contractual obligations
Remainder of 2014	0	[1]		0	[1]
2015	0	[1]		0	[1]
2016	0	[1]		0	[1]
2017	0	[1]		0	[1]
2018	138,000,000	[1]		138,000,000	[1]
Thereafter	0	[1]		0	[1]
Contractual Obligation	138,000,000	[1]		138,000,000	[1]
Interest payments related to convertible notes
Contractual obligations
Remainder of 2014	776,000	[1]		776,000	[1]
2015	1,553,000	[1]		1,553,000	[1]
2016	1,553,000	[1]		1,553,000	[1]
2017	1,553,000	[1]		1,553,000	[1]
2018	1,552,000	[1]		1,552,000	[1]
Thereafter	0	[1]		0	[1]
Contractual Obligation	$ 6,987,000	[1]		$ 6,987,000	[1]

[1] The above table does not reflect possible payments in connection with uncertain tax benefits of approximately $19.8 million including $17.9 million recorded as a reduction of long-term deferred tax assets and $1.9 million in long-term income taxes payable as of June 30, 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. The amount includes the amended Ohio lease and the amended Sunnyvale lease.

[3] The Company has commitments with various software vendors for non-cancellable agreements generally having terms longer than one year.

[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 last payment of CRI retention bonuses was paid in cash during the second quarter of 2014 except for $1.5 million payable to a designated charitable organization as a result of forfeitures by employees.