Fair Value Measurements (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2017 USD ($)	Dec. 31, 2018 USD ($) item	Dec. 31, 2017 USD ($)
Fair Value Measurements
Number of employees covered under life insurance policies \| item		58
Combined face value of life insurance policies		$ 42,000
Cash surrender value		3,300	$ 3,100
Reconciliation of the fair value of contingent earn-out obligations that use significant unobservable inputs (Level 3)
Goodwill impairment	$ 1,100		1,105
Contingent earn-out obligations
Reconciliation of the fair value of contingent earn-out obligations that use significant unobservable inputs (Level 3)
Balance at beginning of year	$ 2,531	7,993	2,531
Issuances		4,366	11,755
Settlements		(7,050)	(2,578)
Adjustments to fair value		(2,066)	3,715
Balance at end of period		7,375	7,993
Recurring basis \| Total
Fair Value Measurements
Cash and cash equivalents		45,620	36,542
Life insurance—cash surrender value		3,252	3,128
Contingent earn-out obligations		7,375	7,993
Recurring basis \| Quoted Market Prices In Active Markets for Identical Assets (Level 1)
Fair Value Measurements
Cash and cash equivalents		45,620	36,542
Recurring basis \| Fair Value Measurements at Reporting Date Using Significant Other Observable Inputs (Level 2)
Fair Value Measurements
Life insurance—cash surrender value		3,252	3,128
Recurring basis \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Contingent earn-out obligations		7,375	7,993
Non recurring basis \| Significant Unobservable Inputs (Level 3)
Reconciliation of the fair value of contingent earn-out obligations that use significant unobservable inputs (Level 3)
Goodwill impairment		$ 0	$ 1,100

Fair value, as of the balance sheet date, of potential cash payments under the contingent consideration arrangement.

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- Definition

Represents the face amount of life insurance policies taken by the entity for their employees.

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Represents the number of employees covered under life insurance policy contracts.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

+ References

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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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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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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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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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Amount of issuances 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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Amount of settlements 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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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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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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