Commitments and Contingencies - Summary of Remaining Aggregate Lease Commitments Under Operating Leases Having Initial Non-Cancelable Terms in Excess of One Year (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Operating Leased Assets [Line Items]
2015	$ 49,359
2016	46,048
2017	42,947
2018	38,673
2019	31,460
Thereafter	108,184
Total	316,671
Aircraft [Member]
Operating Leased Assets [Line Items]
2015	45,379
2016	42,885
2017	40,595
2018	36,914
2019	30,262
Thereafter	106,035
Total	302,070
Other [Member]
Operating Leased Assets [Line Items]
2015	3,980
2016	3,163
2017	2,352
2018	1,759
2019	1,198
Thereafter	2,149
Total	$ 14,601

Commitments and Contingencies - Summary of Remaining Aggregate Lease Commitments Under Operating Leases Having Initial Non-Cancelable Terms in Excess of One Year (Detail) (USD $)
In Thousands, unless otherwise specified

Dec. 31, 2014

Operating Leased Assets [Line Items]

$ 49,359us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent

2016

46,048us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears

2017

42,947us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears

2018

38,673us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears

2019

31,460us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears

Thereafter

108,184us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter

Total

316,671us-gaap_OperatingLeasesFutureMinimumPaymentsDue

Aircraft [Member]

Operating Leased Assets [Line Items]

2015

45,379us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent
/ us-gaap_AircraftTypeAxis
= phii_AircraftMember

2016

42,885us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears
/ us-gaap_AircraftTypeAxis
= phii_AircraftMember

2017

40,595us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears
/ us-gaap_AircraftTypeAxis
= phii_AircraftMember

2018

36,914us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears
/ us-gaap_AircraftTypeAxis
= phii_AircraftMember

2019

30,262us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears
/ us-gaap_AircraftTypeAxis
= phii_AircraftMember

Thereafter

106,035us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter
/ us-gaap_AircraftTypeAxis
= phii_AircraftMember

Total

302,070us-gaap_OperatingLeasesFutureMinimumPaymentsDue
/ us-gaap_AircraftTypeAxis
= phii_AircraftMember

Other [Member]

Operating Leased Assets [Line Items]

2015

3,980us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_AssetsHeldUnderCapitalLeasesMember

2016

3,163us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_AssetsHeldUnderCapitalLeasesMember

2017

2,352us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_AssetsHeldUnderCapitalLeasesMember

2018

1,759us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_AssetsHeldUnderCapitalLeasesMember

2019

1,198us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_AssetsHeldUnderCapitalLeasesMember

Thereafter

2,149us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_AssetsHeldUnderCapitalLeasesMember

Total

$ 14,601us-gaap_OperatingLeasesFutureMinimumPaymentsDue
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_AssetsHeldUnderCapitalLeasesMember

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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