Intangible Assets and Goodwill - Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Goodwill
Impairment charge	$ 0	$ 0	$ 0	$ 0
Goodwill, Beginning Balance			376,132
Measurement period adjustments			(19,318)
Goodwill, Ending Balance	356,814		356,814
GBG
Goodwill
Goodwill, Ending Balance	$ 348,407		$ 348,407

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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- Definition

Total loss recognized during the period from the impairment of goodwill plus the loss recognized in the period resulting from the impairment of the carrying amount of intangible assets, other than goodwill.

+ References

No definition available.

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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
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- Definition

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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