Fair Value Measurements (Details) - Recurring - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Fair Value Measurements
Contingent consideration, current	$ 2,352	$ 0
Contingent consideration, non-current	2,275	4,477
Nonfinancial Liabilities Fair Value Disclosure	4,627	4,477
Level 1
Fair Value Measurements
Cash equivalents	171,254	192,207
Total assets	171,254	192,207
Contingent consideration, current	0	0
Contingent consideration, non-current	0	0
Nonfinancial Liabilities Fair Value Disclosure	0	0
Fair Value, Inputs, Level 2 [Member]
Fair Value Measurements
Cash equivalents	0	0
Contingent consideration, current	0	0
Contingent consideration, non-current	0	0
Nonfinancial Liabilities Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 [Member]
Fair Value Measurements
Cash equivalents	0	0
Contingent consideration, current	2,352	0
Contingent consideration, non-current	2,275	4,477
Nonfinancial Liabilities Fair Value Disclosure	4,627	4,477
Total fair value
Fair Value Measurements
Cash equivalents	171,254	192,207
Total assets	$ 171,254	$ 192,207

Commitments, Current, Fair Value Disclosure

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- Definition

Commitments, Noncurrent, Fair Value Disclosure

+ References

No definition available.

+ Details

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

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.

+ References

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- Definition

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.

+ References

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- Definition

Fair value of obligations not classified as financial liabilities. Includes, but is not limited to, accounts payable and accrued liabilities, commitments, obligations, and other liabilities.

+ References

No definition available.

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