Commitments and Contingencies - Additional Information (Detail) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2016 USD ($) Aircraft	Dec. 31, 2016 USD ($) Land_Parcel	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Long-term Purchase Commitment [Line Items]
Aircraft and real estate rental expense		$ 53,581	$ 53,718	$ 52,698
Aggregate amount of guarantees and bonds	$ 1,000	1,000
Total aircraft deposits	4,818	4,818	3,568
Aggregate estimated probable liability environmental matters	$ 150	$ 150
Number of parcels of land exists | Land_Parcel		2
Affiliated Entity [Member]
Long-term Purchase Commitment [Line Items]
Aircraft and real estate rental expense		$ 0	$ 0	$ 500
2017 [Member]
Long-term Purchase Commitment [Line Items]
Aggregate purchase price for aircraft		55,700
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
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