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Acquisition and Disposition (Details) - USD ($)			3 Months Ended	12 Months Ended	16 Months Ended
Acquisition and Disposition (Details) - USD ($)	Mar. 04, 2016	Mar. 16, 2015	Mar. 31, 2016	Dec. 31, 2014	Jun. 30, 2016	Dec. 31, 2015
Recognized amounts of tangible assets and liabilities:
Goodwill					$ 73,179,000	$ 69,699,000
Aleutian Consulting Inc
Total consideration
Cash consideration per purchase agreement	$ 3,500,000
Recognized amounts of tangible assets and liabilities:
Goodwill	$ 3,500,000
3Q Digital Inc
Acquisition and Disposition
Estimate of potential undiscounted future contingent consideration payments, low end of range		$ 0
Estimate of potential undiscounted future contingent consideration payments, high end of range		35,000,000
Total consideration
Cash consideration per purchase agreement		30,245,000
Estimated fair value of contingent consideration		17,940,000
Business Combination, Consideration Transferred		48,185,000
Recognized amounts of tangible assets and liabilities:
Current assets		4,135,000
Property and equipment		164,000
Other assets		389,000
Current liabilities		(822,000)
Total tangible assets and liabilities:		3,866,000
Identifiable intangible assets		4,773,000
Goodwill		41,845,000
Total		50,484,000
Deferred tax adjustment		2,298,000
Increase (decrease) in contingent consideration			$ (247,000)
3Q Digital Inc \| Customer relationships
Recognized amounts of tangible assets and liabilities:
Identifiable intangible assets		$ 4,300,000
Amortization period		7 years
3Q Digital Inc \| Tradenames and trademarks
Recognized amounts of tangible assets and liabilities:
Identifiable intangible assets		$ 300,000
Amortization period		2 years
3Q Digital Inc \| Non-compete agreements
Recognized amounts of tangible assets and liabilities:
Identifiable intangible assets		$ 200,000
Amortization period		3 years
3Q Digital Inc \| Level 3 \| Contingent Consideration
Reconciliation of accrued earnout consideration
Accretion of interest					3,366,000
Adjustment to fair value					(247,000)
Contingent consideration		$ 17,940,000			$ 21,059,000
B2B research business \| Maximum
Sale of business
Percent of total Company revenue (less than)				5.00%