v3.7.0.1

Commitments and Contingencies - Additional Information (Detail) $ in Thousands | 3 Months Ended
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Mar. 31, 2017 USD ($) Aircraft Land_Parcel
Long-term Purchase Commitment [Line Items] |
Total aircraft deposits | $ 4,900
Aggregate estimated probable liability environmental matters | $ 150
Number of parcels of land exists | Land_Parcel | 2
Aggregate commitments under operating leases | $ 219,600
Operational lease payable | 34,700
Lease commitment for aircraft | 205,000
Facility lease commitments | 14,600
2017 [Member] |
Long-term Purchase Commitment [Line Items] |
Aggregate purchase price for aircraft | 37,100
2018 [Member] |
Long-term Purchase Commitment [Line Items] |
Aggregate purchase price for aircraft | 127,000
2019 [Member] |
Long-term Purchase Commitment [Line Items] |
Aggregate purchase price for aircraft | 129,000
2020 [Member] |
Long-term Purchase Commitment [Line Items] |
Aggregate purchase price for aircraft | 22,700
Heavy Aircraft [Member] |
Long-term Purchase Commitment [Line Items] |
Aggregate purchase price for aircraft | $ 17,000
Number of aircraft purchased | Aircraft | 1
Medium Aircraft [Member] | Oil and Gas [Member] |
Long-term Purchase Commitment [Line Items] |
Number of aircrafts acquired under contract | Aircraft | 2
Purchase commitment for aircraft | $ 17,900

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