v3.5.0.2

Commitments and Contingencies - Additional Information (Detail) $ in Millions |  | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Oct. 01, 2016 USD ($) Aircraft | Sep. 30, 2016 USD ($) Aircraft | Sep. 30, 2016 USD ($) Land_Parcel | Dec. 31, 2015 Aircraft | Dec. 31, 2014 Aircraft
Long-term Purchase Commitment [Line Items] |  |  |  |  |
Number of aircrafts delivered | Aircraft |  |  |  | 1 |
Total aircraft deposits |  | $ 2.8 | $ 2.8 |  |
Aggregate estimated probable liability environmental matters |  | 0.2 | $ 0.2 |  |
Number of parcels of land exists | Land_Parcel |  |  | 2 |  |
Aggregate commitments under operating leases |  | 239.0 | $ 239.0 |  |
Operational lease payable |  | 12.0 | 12.0 |  |
Lease commitment for aircraft |  | 226.2 | 226.2 |  |
Facility lease commitments |  | 12.8 | 12.8 |  |
2016 [Member] |  |  |  |  |
Long-term Purchase Commitment [Line Items] |  |  |  |  |
Aggregate purchase price for aircraft |  |  | 50.3 |  |
2017 [Member] |  |  |  |  |
Long-term Purchase Commitment [Line Items] |  |  |  |  |
Aggregate purchase price for aircraft |  |  | 55.7 |  |
2018 [Member] |  |  |  |  |
Long-term Purchase Commitment [Line Items] |  |  |  |  |
Aggregate purchase price for aircraft |  |  | 127.0 |  |
2019 [Member] |  |  |  |  |
Long-term Purchase Commitment [Line Items] |  |  |  |  |
Aggregate purchase price for aircraft |  |  | 150.4 |  |
2020 [Member] |  |  |  |  |
Long-term Purchase Commitment [Line Items] |  |  |  |  |
Aggregate purchase price for aircraft |  |  | $ 22.7 |  |
Heavy Aircraft [Member] |  |  |  |  |
Long-term Purchase Commitment [Line Items] |  |  |  |  |
Option to purchase additional number of aircrafts | Aircraft |  |  |  |  | 6
Number of aircraft orders cancelled previously scheduled for delivery | Aircraft |  |  |  | 4 |
Aggregate purchase price for aircraft |  | $ 26.7 |  |  |
Number of aircraft purchased | Aircraft |  | 1 |  |  |
Medium Aircraft [Member] | Subsequent Event [Member] | Oil and Gas [Member] |  |  |  |  |
Long-term Purchase Commitment [Line Items] |  |  |  |  |
Number of aircrafts acquired under contract | Aircraft | 2 |  |  |  |
Purchase commitment for aircraft | $ 19.9 |  |  |  |

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