v3.6.0.2

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 |  |  |

X
- Definition Deposits on equipment purchases noncurrent. + References No definition available. + Details
Name: | phii_DepositsOnEquipmentPurchasesNoncurrent
Namespace Prefix: | phii_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Number of aircrafts acquired under contract. + References No definition available. + Details
Name: | phii_NumberOfAircraftsAcquiredUnderContract
Namespace Prefix: | phii_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of land parcels. + References No definition available. + Details
Name: | phii_NumberOfLandParcels
Namespace Prefix: | phii_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- 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
Name: | us-gaap_AccrualForEnvironmentalLossContingencies
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Fair value portion of guarantee, including, but not limited to, financial standby letter of credit, fair value guarantee, guarantee of collection of scheduled contractual cash flows from financial assets, and contracts that contingently require the guarantor to make payments or perform services. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12201-110248 + Details
Name: | us-gaap_GuaranteesFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The minimum amount the entity agreed to spend under the long-term purchase commitment. + References No definition available. + Details
Name: | us-gaap_LongTermPurchaseCommitmentAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- 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
Name: | us-gaap_LongTermPurchaseCommitmentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717 + Details
Name: | us-gaap_OperatingLeasesRentExpenseNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- 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
Name: | us-gaap_PaymentsToAcquireProductiveAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_AffiliatedEntityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis=phii_TwoThousandAndSeventeenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis=phii_TwoThousandAndEighteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis=phii_TwoThousandAndNineteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongTermPurchaseCommitmentByCategoryOfItemPurchasedAxis=phii_TwoThousandAndTwentyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AircraftTypeAxis=phii_MediumAircraftMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=phii_OilAndGasMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |