Acquisition and Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Acquisition and Goodwill [Abstract]
Acquisition	$ 0	$ (100,763)
Goodwill	$ 16,400	16,400	$ 16,400
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets		$ (84,600)

Acquisition and Goodwill [Abstract]

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- Definition

Amount of assets acquired at the acquisition date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
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