Acquisition (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Mar. 19, 2012
Schedule of total purchase price
Cash, accounts receivable and other assets		$ 914
Deferred tax asset, short term		1,829
Goodwill	31,700	31,710
Intangible assets		21,770
Accrued expenses and deferred revenue		(2,413)
Deferred tax liability, long term		(4,238)
Total purchase price		$ 49,572