v3.7.0.1

Stock-Based Compensation - Additional Information (Detail) - shares	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Time-based Restricted Units [Member]
Stock Based Compensation [Line Items]
Restricted units awarded to managers	29,351
Performance-based Restricted Units [Member]
Stock Based Compensation [Line Items]
Restricted units awarded to managers	366,399	303,061

X

- Definition

Stock Based Compensation [Line Items]

+ References

No definition available.

+ Details

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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

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- Details

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X

- Details

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Balance Type:
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