Income Taxes - Summary of Change in Valuation Allowance (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Deferred Tax Assets, Valuation Allowance [Roll Forward]
Beginning balance	$ 2,471	$ 2,153	$ 641
Additions due to acquisitions	36,410
(Deductions) additions, net	(7,058)	318	1,512
Ending balance	$ 31,823	$ 2,471	$ 2,153

Deferred Tax Assets, Valuation Allowance [Roll Forward]

No definition available.

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- Definition

Valuation allowance deferred tax asset change in amount due to acquisitions.

+ References

No definition available.

+ Details

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

+ Details

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- Definition

Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84176650&loc=d3e32123-109318

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