Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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The amount of liability arising from an inherited contingency (as defined) which has been recognized as of the acquisition date.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Business Acquisition (Purchase Price Allocation) (Details) - USD ($) $ in Thousands		9 Months Ended
	Apr. 02, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Business Acquisition [Line Items]
Goodwill		$ 64,489		$ 52,990
Net cash consideration		$ 5,794	$ 80,131
Huntington Steele, LLC
Business Acquisition [Line Items]
Cash	$ 125
Goodwill	11,499
Other assets	15
Current liabilities	(230)
Contingent consideration	(12,120)
Net cash consideration	5,794
Huntington Steele, LLC \| Client relationships
Business Acquisition [Line Items]
Identifiable intangible assets	$ 6,180
Estimated Useful Life	12 years
Huntington Steele, LLC \| Trade names
Business Acquisition [Line Items]
Identifiable intangible assets	$ 450
Estimated Useful Life	7 years