v3.4.0.3

Stock-Based Compensation - Additional Information (Detail) - shares	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Time-based Restricted Stock Units [Member]
Stock Based Compensation [Line Items]
Restricted stock units awarded to managers		18,930
Performance-based Restricted Stock Units [Member]
Stock Based Compensation [Line Items]
Restricted stock units awarded to managers	303,061	151,566

X

- Definition

Stock Based Compensation [Line Items]

+ References

No definition available.

+ Details

Name:	phii_StockBasedCompensationLineItems
Namespace Prefix:	phii_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

+ Details

Name:	us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_AwardTypeAxis=phii_TimeBasedAwardsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_AwardTypeAxis=phii_PerformanceBasedAwardsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: