Debt instrument interest rate percentage amortization, year one.

No definition available.

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- Definition

Debt instrument interest rate percentage amortization, year thereafter.

+ References

No definition available.

+ Details

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- Definition

Debt instrument interest rate percentage amortization, year three.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Debt instrument interest rate percentage amortization, year two.

+ References

No definition available.

+ Details

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

- Definition

Debt instrument, prepayment percentage of principal amount.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Debt instrument prepayment percentage of principal amount fourth year and thereafter.

+ References

No definition available.

+ Details

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Namespace Prefix:	phii_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument prepayment percentage of principal amount including accrued interest.

+ References

No definition available.

+ Details

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Namespace Prefix:	phii_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument prepayment percentage of principal amount second year.

+ References

No definition available.

+ Details

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

- Definition

Debt instrument prepayment percentage of principal amount third year.

+ References

No definition available.

+ Details

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Namespace Prefix:	phii_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Financial instrument covenant minimum liquidity.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Number of Aircraft Securing Debt Agreement

+ References

No definition available.

+ Details

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Namespace Prefix:	phii_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of required prepayment cash proceeds from debt issuance.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	instant

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

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

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- Details

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- Details

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- Details

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Debt - Additional Information (Detail)			6 Months Ended
Debt - Additional Information (Detail)	Aug. 02, 2019 USD ($)	Mar. 13, 2019 USD ($) Air-craft	Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 28, 2018 USD ($)	Mar. 17, 2014 USD ($)
Debt Instrument [Line Items]
Long-term Debt, Gross			$ 700,000,000	$ 630,000,000
Letters of credit outstanding under the facility			19,700,000	$ 19,800,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Letters of credit outstanding under the facility			$ 7,600,000
Term Loan [Member]
Debt Instrument [Line Items]
Number of Aircraft Securing Debt Agreement \| Air-craft		91
Term Loan [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		6.00%
Term Loan [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		5.00%
5.25% Senior Notes due March 15, 2019 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate on debt			5.25%	5.25%		5.25%
Debt, maturity date			Mar. 15, 2019
Long-term Debt, Gross			$ 500,000,000	$ 500,000,000
Related party term loan, amount issued						$ 500,000,000
6% Blue Torch Finance, LLC Term Loan [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Debt, maturity date			Mar. 13, 2023
Long-term Debt, Gross		$ 70,000,000	$ 70,000,000
Long-term debt, borrowed amount		$ 70,000,000
6% Blue Torch Finance, LLC Term Loan [Member] \| Term Loan [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate			6.00%
6% Related Party Term Loan [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Interest rate on debt			6.00%
Debt, maturity date			Sep. 28, 2020
Long-term Debt, Gross			$ 130,000,000	$ 130,000,000
Related party term loan, amount issued					$ 130,000,000
Letter of Credit to Secure workers Compensation Policies, Air Medical License, and a Traditional Provider Contract [Member]
Debt Instrument [Line Items]
Letters of credit outstanding under the facility			$ 12,100,000
Exit Term Loan [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 225,000,000
Debt Instrument, Basis Spread on Variable Rate	0.50%
Debt instrument maturity period	5 years
Interest rate on debt	2.00%
Debt instrument interest rate percentage amortization, year one	2.50%
Debt instrument interest rate percentage amortization, year two	2.50%
Debt instrument interest rate percentage amortization, year three	5.00%
Debt instrument interest rate percentage amortization, thereafter	7.50%
Percentage of required prepayment cash proceeds from debt issuance	100.00%
Percentage of principal amount prepaid	1.00%
Percentage of principal amount prepaid including accrued interest	2.00%
Percentage of principal amount prepaid second year	2.00%
Percentage of principal amount prepaid third year	1.00%
Percentage of principal amount prepaid fourth year and thereafter	0.00%
Financial covenant minimum liquidity	$ 20,000,000
Exit Term Loan [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Interest rate on debt	7.00%
Debt Instrument, Basis Spread on Variable Rate	1.00%
Exit Term Loan [Member] \| Base Rate [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Interest rate on debt	6.00%
Exit Term Loan [Member] \| Federal Funds Effective Rate [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.50%
Exit Term Loan [Member] \| Floor Rate [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.00%