Restructuring Obligations and Other Charges (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended							6 Months Ended
	Sep. 30, 2012	Sep. 30, 2012	Sep. 30, 2009	Sep. 30, 2009 General and Administrative Expense [Member]	Sep. 30, 2012 Facilities [Member]		Sep. 30, 2012 Severance [Member]		Jun. 30, 2012 Severance [Member] Sales and Marketing Expense [Member]	Jun. 30, 2012 Severance [Member] General and Administrative Expense [Member]
Restructuring Cost and Reserve [Line Items]
Reduction in number of employees	190
Percentage of reduction in employees (in hundredths)	15.00%
Restructuring charge		$ 172		$ 1,300	$ 0	[1]	$ 172	[2]	$ 142,000	$ 30,000
Percentage of facility impaired due to restructuring (in hundredths)			46.00%
Restructuring and related expenses [Roll Forward]
Restructuring obligations, December 31, 2011		210			208	[1]	2	[2]
Restructuring costs incurred in 2012		172		1,300	0	[1]	172	[2]	142,000	30,000
Cash payments		(382)			(208)	[1]	(174)	[2]
Restructuring obligations, June 30, 2012	$ 0	$ 0			$ 0	[1]	$ 0	[2]

[1] Facilities costs include obligations under non-cancelable leases for facilities that we no longer occupy, as well as penalties associated with early terminations of leases and disposal of fixed assets. No sublease income has been included because subleasing is not permitted under the terms of our lease.

[2] Severance costs include those expenses related to severance pay and related employee benefit obligations.