Asset Impairment (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 61,600	$ 61,643	$ 0	$ 0
Intangible assets	15,500	15,557	0	0
Aircraft and related inventory	$ 23,200	31,824	368	407
Total		$ 109,024	$ 368	$ 407

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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No definition available.

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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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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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-Topic 230
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- Definition

The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value.

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