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

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

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Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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

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Percentage of principal amount of debt redeemed.

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Description of covenants that limit or prohibit certain actions or activities without the lender's prior consent within a specified period of time or until certain specified targets are achieved for example, reduction of the debt or an increase in net worth to a specified amount).

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

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The cash inflow from a long-term borrowing made from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Proceeds from Advances from Affiliates.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Debt - Additional Information (Detail) - USD ($)		9 Months Ended
Debt - Additional Information (Detail) - USD ($)	Sep. 28, 2018	Sep. 30, 2018	Dec. 31, 2017	Mar. 17, 2014
Debt Instrument [Line Items]
Letters of credit outstanding under the facility		$ 19,800,000	$ 19,600,000
5.25% Senior Notes due March 15, 2019 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate on debt		5.25%		5.25%
Maturity date of Senior notes payable		Mar. 15, 2019
Debt instrument interest rate term		Interest is payable semi-annually on March 15 and September 15 of each year.
Debt instrument restrictive covenants		The indenture governing the 2019 Notes (the “2019 Indenture”) contains, among other things, certain restrictive covenants, including limitations on incurring indebtedness, creating liens, selling assets and entering into certain transactions with affiliates. The covenants also limit PHI’s ability to, among other things, pay cash dividends on common stock, repurchase or redeem common or preferred equity, prepay subordinated debt and make certain investments.
Percentage of principal amount redeemed		101.00%
Related party term loan, amount issued				$ 500,000,000
6% Related Party Term Loan [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Interest rate on debt		6.00%
Related party term loan, amount issued	$ 130,000,000
Proceeds from related party debt	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		$ 12,000,000
Letter of Credit to Guaranty International Contract Performance [Member]
Debt Instrument [Line Items]
Letters of credit outstanding under the facility		$ 7,800,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Repayments of senior secured revolving credit facility, including accrued interest	$ 122,700,000