v3.7.0.1

Commitments and Contingencies - Additional Information (Detail) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 USD ($) Aircraft | Jun. 30, 2017 USD ($) Land_Parcel
Long-term Purchase Commitment [Line Items] |  |
Purchase commitment for aircraft |  | $ 0
Total aircraft deposits | $ 500,000 | 500,000
Aggregate estimated probable liability environmental matters | 150,000 | $ 150,000
Number of parcels of land exists | Land_Parcel |  | 2
Aggregate commitments under operating leases | 205,200,000 | $ 205,200,000
Operational lease payable | 21,600,000 | 21,600,000
Lease commitment for aircraft | 191,400,000 | 191,400,000
Facility lease commitments | 13,800,000 | 13,800,000
2017 [Member] |  |
Long-term Purchase Commitment [Line Items] |  |
Aggregate purchase price for aircraft |  | 18,500,000
2018 [Member] |  |
Long-term Purchase Commitment [Line Items] |  |
Aggregate purchase price for aircraft |  | 127,000,000
2019 [Member] |  |
Long-term Purchase Commitment [Line Items] |  |
Aggregate purchase price for aircraft |  | 129,000,000
2020 [Member] |  |
Long-term Purchase Commitment [Line Items] |  |
Aggregate purchase price for aircraft |  | $ 22,700,000
Heavy Aircraft [Member] |  |
Long-term Purchase Commitment [Line Items] |  |
Aggregate purchase price for aircraft | $ 17,000,000 |
Number of aircraft purchased | Aircraft | 1 |

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- Definition Aggregate commitments under operating leases. + References No definition available. + Details
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- Definition Deposits on equipment purchases noncurrent. + References No definition available. + Details
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- Definition Facility lease commitments. + References No definition available. + Details
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- Definition Lease commitment for aircraft. + References No definition available. + Details
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- Definition Number of aircraft purchased. + References No definition available. + Details
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- Definition Number of land parcels. + References No definition available. + Details
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- Definition Operational lease payable. + References No definition available. + Details
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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346 + Details
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- Definition The minimum amount the entity agreed to spend under the long-term purchase commitment. + References No definition available. + Details
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- Definition The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585 + Details
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- Details
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