Acquisitions (Details) (USD $)	12 Months Ended	1 Months Ended		1 Months Ended	12 Months Ended		1 Months Ended			1 Months Ended		1 Months Ended
	Dec. 31, 2011 Customer related intangibles Y	Jun. 30, 2011 Ross Smith Energy Group Ltd. ("RSEG") Y	Jun. 03, 2011 Ross Smith Energy Group Ltd. ("RSEG") client	Jun. 30, 2011 Ross Smith Energy Group Ltd. ("RSEG") Customer related intangibles Y	Dec. 31, 2011 Ross Smith Energy Group Ltd. ("RSEG") Customer related intangibles Y	Jun. 03, 2011 Ross Smith Energy Group Ltd. ("RSEG") Customer related intangibles	Oct. 31, 2010 Majestic Research Corp.	Dec. 31, 2011 Majestic Research Corp.	Oct. 25, 2010 Majestic Research Corp. sector	Oct. 31, 2010 Majestic Research Corp. Customer related intangibles Y	Oct. 25, 2010 Majestic Research Corp. Customer related intangibles	Jul. 31, 2007 RedSky Financial, LLC	Jan. 31, 2011 RedSky Financial, LLC	Dec. 31, 2010 RedSky Financial, LLC	Dec. 31, 2009 RedSky Financial, LLC
Acquisitions
Minimum number of clients			200
Number of industry sectors covered									17
Purchase price adjustment								$ 144,000
Cash paid related to business acquisition			38,600,000						53,200,000			22,500,000
Converted equity awards									3,000,000
Acquisition related costs		700,000					2,400,000					400,000
Costs related with termination of a distribution agreement, net			1,800,000
Costs related with termination of a distribution agreement, recovery from former owners			1,000,000
Purchase price allocation
Cash			2,540,000						7,151,000
Accounts receivable, net			1,422,000						3,194,000
Customer related intangible asset			6,950,000		7,000,000	7,000,000			12,500,000		12,500,000
Deferred tax assets									4,027,000
Other assets									1,133,000
Accounts payable and accrued liabilities			(1,505,000)						(10,098,000)
Deferred income			(2,151,000)						(5,093,000)
Deferred tax liabilities									(5,182,000)
Other liabilities									(134,000)
Other assets and liabilities, net			611,000
Goodwill			30,715,000						48,717,000
Total purchase price			38,582,000						56,215,000
Number of years over which goodwill is deductible for tax purposes		15
Useful lives (in years)	13.1			10	10					12
Disclosures pertaining to cost of acquisition
Percentage of interest acquired												100.00%
Contingent payment															2,500,000
Contingent payment included in the purchase price															1,900,000
Purchase price including acquisition costs															22,900,000
Guaranteed amount payable															7,500,000
Portion of guaranteed payment included in purchase price															5,600,000
Initial portion of guaranteed payment considered compensatory														1,900,000
Decrease in value of guaranteed payment considered compensatory														100,000
Portion of guaranteed payment considered compensatory, as adjusted														1,800,000
Guaranteed amount paid													7,400,000
Maximum additional contingent payments														12,500,000
Portion of contingent payment to be recognized as an expense														$ 7,000,000	$ 600,000