Amount recognized for the passage of time, typically for liabilities, that have been discounted to their net present values. Excludes accretion associated with asset retirement obligations.

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-Name Accounting Standards Codification
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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For contingent consideration arrangements and indemnification assets recognized in connection with a business combination, this element represents an estimate of the low-end of the potential range (undiscounted) of the consideration which may be paid.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Acquisition and Disposition (Details) - USD ($) $ in Thousands		6 Months Ended
	Mar. 04, 2016	Jun. 30, 2017	Jun. 30, 2016	Mar. 16, 2015
Reconciliation of accrued earnout consideration
Interest accretion on contingent consideration		$ 2,081	$ 1,029
Aleutian Consulting Inc
Acquisitions
Payments to acquire businesses	$ 3,500
3Q Digital Inc
Acquisitions
Contingent consideration, minimum potential payment				$ 0
Contingent consideration, maximum potential payment				$ 35,000
3Q Digital Inc \| Level 3 \| Contingent Consideration
Reconciliation of accrued earnout consideration
Accrued contingent consideration at beginning of period		29,725
Interest accretion on contingent consideration		2,081
Adjustments to fair value		0
Accrued contingent consideration at end of period		$ 31,806