Basis of Presentation (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended				12 Months Ended
	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2012
schedule gain on sale business ConferencePlus [Line Items]
Pretax gain on sale of business	$ 0	$ 0	$ 46	$ 31,608	$ 31,654
Discontinued Operation, Tax Effect of Income (Loss) from Disposal of Discontinued Operation					(12,359)
Gain (Loss) on Sale of Business					20,489
Sale of Conference Plus Inc [Member]
schedule gain on sale business ConferencePlus [Line Items]
cash proceeds sale of subsidiary					40,331
Less from Net Value of Assets and Liabilities Sold or Transferred and Transaction Costs					(7,483)
Pretax gain on sale of business					32,848
Discontinued Operation, Tax Effect of Income (Loss) from Disposal of Discontinued Operation					(12,359)
Gain (Loss) on Sale of Business					$ 20,489

Amount of tax expense or benefit on gain (loss), not previously recognized, resulting from the sale of a business component.