v3.8.0.1

Segment Information - Additional Information (Detail) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 States Aircraft Location Segment | Sep. 30, 2016
Segment Reporting Information [Line Items] |  |  |  |
Number of reportable segments | Segment |  |  | 3 |
National Science Foundation [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Number of aircraft assigned |  |  | 6 |
Hospitals Contracts [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Segment revenue | 15.00% | 27.00% | 17.00% | 29.00%
Fixed Term Customer Contract [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Segment revenue | 89.00% | 92.00% | 90.00% | 92.00%
Contracted Customers [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Segment revenue |  |  | 10.00% | 8.00%
Minimum [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Term of contract |  |  | 1 year |
Maximum [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Term of contract |  |  | 7 years |
Oil and Gas [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Number of aircraft available for use |  |  | 126 |
Segment revenue | 50.00% | 49.00% | 51.00% | 51.00%
Oil and Gas [Member] | Minimum [Member] | Major Customer [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Working period with major customers |  |  | 30 years |
Oil and Gas [Member] | Minimum [Member] | ENI Petroleum [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Working period with major customers |  |  | 15 years |
Air Medical [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Segment revenue | 47.00% | 47.00% | 45.00% | 45.00%
Number of aircraft assigned |  |  | 105 |
Number of states in which company operates aircrafts | States |  |  | 18 |
Locations in which company operates Aircrafts | Location |  |  | 72 |
Technical Services [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Segment revenue | 3.00% | 4.00% | 4.00% | 4.00%

X
- Definition Locations in which company operates aircrafts. + References No definition available. + Details
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- Definition Number of aircraft available for use. + References No definition available. + Details
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- Definition Number Of Aircrafts Assigned + References No definition available. + Details
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- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. + References No definition available. + Details
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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 No definition available. + Details
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- Details
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- Details
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- Details
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- Details
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- Details
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