v3.3.1.900

Subsequent Events - Additional Information (Detail) $ in Millions	1 Months Ended	12 Months Ended
	Jan. 31, 2016 USD ($) RetirementPlans Employees	Dec. 31, 2015 RetirementPlans
Subsequent Event [Line Items]
Number of voluntary employee retirement program (VERP) | RetirementPlans		3
Subsequent Event [Member]
Subsequent Event [Line Items]
Number of voluntary employee retirement program (VERP) | RetirementPlans	1
Subsequent Event [Member] | Voluntary Employee Retirement Package [Member]
Subsequent Event [Line Items]
Qualifying age	64 years
Subsequent Event [Member] | Voluntary Employee Retirement Package [Member] | Maximum [Member]
Subsequent Event [Line Items]
Severance costs | $	$ 3.1
Subsequent Event [Member] | Voluntary Furlough Program [Member]
Subsequent Event [Line Items]
Severance costs | $	$ 0.4
Number of employees accepted VERP | Employees	26

X

- Definition

Number of employees accepted voluntary retirement.

+ References

No definition available.

+ Details

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

X

- Definition

Number of voluntary employee retirement program.

+ References

No definition available.

+ Details

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

X

- Definition

Postretirement Benefit Plan Qualifying Age

+ References

No definition available.

+ Details

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

X

- Definition

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 5.P.3)
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140864-122747

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)(10)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 5
-Section P
-Subsection 3, 4

+ Details

Name:	us-gaap_SeveranceCosts1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

Name:	us-gaap_SubsequentEventLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=phii_VoluntaryEmployeeRetirementPackageMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=phii_VoluntaryFurloughProgramMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: