Contract Termination Notice Period

No definition available.

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Namespace Prefix:	phii_
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Balance Type:	na
Period Type:	duration

- Definition

Locations in which company operates aircrafts.

+ References

No definition available.

+ Details

Name:	phii_LocationsInWhichCompanyOperatesAircrafts
Namespace Prefix:	phii_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of aircraft available for use.

+ References

No definition available.

+ Details

Name:	phii_NumberOfAircraftAvailableForUse
Namespace Prefix:	phii_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number Of Aircrafts Assigned

+ References

No definition available.

+ Details

Name:	phii_NumberOfAircraftsAssigned
Namespace Prefix:	phii_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of operating states.

+ References

No definition available.

+ Details

Name:	phii_NumberOfOperatingStates
Namespace Prefix:	phii_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Property plant and equipment number of remaining aircraft in segment.

+ References

No definition available.

+ Details

Name:	phii_PropertyPlantAndEquipmentNumberOfRemainingAircraftInSegment
Namespace Prefix:	phii_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

Term of contract.

+ References

No definition available.

+ Details

Name:	phii_TermOfContract
Namespace Prefix:	phii_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Working period with major customers.

+ References

No definition available.

+ Details

Name:	phii_WorkingPeriodWithMajorCustomers
Namespace Prefix:	phii_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13531-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13537-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

+ Details

Name:	us-gaap_ConcentrationRiskPercentage1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of aircraft sold by the entity during the period.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- 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

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Data Type:	xbrli:stringItemType
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- Details

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- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CustomerConcentrationRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesRevenueNetMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MajorCustomersAxis=phii_SpotMarketandAdHocFlightCustomerContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MajorCustomersAxis=phii_HospitalsContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	srt_RangeAxis=srt_MinimumMember
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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_ProductConcentrationRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MajorCustomersAxis=phii_EniPetroleumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=phii_AirMedicalMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=phii_TechnicalServicesMember
Namespace Prefix:
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Segment Information - Additional Information (Detail)	3 Months Ended		6 Months Ended
Segment Information - Additional Information (Detail)	Jun. 30, 2019 Air-craft	Jun. 30, 2018	Jun. 30, 2019 Air-craft Segment State Location	Jun. 30, 2018
Segment Reporting Information [Line Items]
Number of reportable segments \| Segment			3
Number of aircraft sold	0
National Science Foundation [Member]
Segment Reporting Information [Line Items]
Number of aircraft assigned			6
Number of aircraft sold			2
Number of remaining aircraft in segment			4
Fixed Term Customer Contract [Member] \| Customer Concentration Risk [Member] \| Sales Revenue Net [Member]
Segment Reporting Information [Line Items]
Segment revenue (percent)	85.00%	87.00%	85.00%	87.00%
Spot Market and Ad Hoc Flight Customer Contracts [Member] \| Customer Concentration Risk [Member] \| Sales Revenue Net [Member]
Segment Reporting Information [Line Items]
Segment revenue (percent)			15.00%
Hospitals Contracts [Member]
Segment Reporting Information [Line Items]
Contract termination notice period			180 days
Hospitals Contracts [Member] \| Customer Concentration Risk [Member] \| Sales Revenue Net [Member]
Segment Reporting Information [Line Items]
Segment revenue (percent)	15.00%	16.00%	17.00%	18.00%
Minimum [Member]
Segment Reporting Information [Line Items]
Term of contract			1 year
Maximum [Member]
Segment Reporting Information [Line Items]
Term of contract			7 years
Oil and Gas [Member]
Segment Reporting Information [Line Items]
Number of aircraft available for use			121
Oil and Gas [Member] \| Product Concentration Risk [Member] \| Sales Revenue Net [Member]
Segment Reporting Information [Line Items]
Segment revenue (percent)	55.00%	57.00%	55.00%	58.00%
Oil and Gas [Member] \| Minimum [Member]
Segment Reporting Information [Line Items]
Working period with major customers			35 years
Oil and Gas [Member] \| Minimum [Member] \| ENI Petroleum [Member]
Segment Reporting Information [Line Items]
Working period with major customers			20 years
Air Medical [Member]
Segment Reporting Information [Line Items]
Number of aircraft assigned			111
Number of states in which company operates aircrafts \| State			18
Locations in which company operates Aircrafts \| Location			81
Air Medical [Member] \| Product Concentration Risk [Member] \| Sales Revenue Net [Member]
Segment Reporting Information [Line Items]
Segment revenue (percent)	42.00%	40.00%	40.00%	38.00%
Air Medical [Member] \| Minimum [Member]
Segment Reporting Information [Line Items]
Contract termination notice period			30 days
Air Medical [Member] \| Maximum [Member]
Segment Reporting Information [Line Items]
Contract termination notice period			180 days
Technical Services [Member] \| Product Concentration Risk [Member] \| Sales Revenue Net [Member]
Segment Reporting Information [Line Items]
Segment revenue (percent)	3.00%	3.00%	5.00%	4.00%