Accrued and Other Current Liabilities - Schedule of Accrued Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Payables and Accruals [Abstract]
Salaries & wages	$ 16,203	$ 14,318
Incentive compensation	11,730	11,617
Income taxes	3,787us-gaap_AccruedIncomeTaxesCurrent	6,790us-gaap_AccruedIncomeTaxesCurrent
Interest	7,891	5,621
Vacation payable	6,112	5,751
Group medical	1,735phii_AccruedGroupMedical	1,516phii_AccruedGroupMedical
Transportations tax	907	1,975
Operating lease	1,227phii_OperatingLease	1,048phii_OperatingLease
Workers compensation	1,185	3,684
Other	2,035	2,211
Total accrued liabilities	$ 52,812	$ 54,531

Accrued group medical.

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- Definition

Operating lease.

+ References

No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.15(5))

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-Topic 944

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 15

-Subparagraph a

-Article 7

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-Name Regulation S-X (SX)

-Number 210

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 720

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6419918&loc=d3e35281-107843

+ Details

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- Definition

Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

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-Publisher SEC

-Name Regulation S-X (SX)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Subparagraph b(1)

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities.

+ References

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- Definition

Carrying value as of the balance sheet date of the obligations incurred through that date and payable for employees' services provided.

+ References

+ Details

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable for unused vacation time owed to employees based on the entity's vacation benefit given to its employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.15(5))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Topic 710

-SubTopic 10

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-URI http://asc.fasb.org/extlink&oid=6409733&loc=d3e19396-108361

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- Definition

Amount of accrued but unpaid interest on deposit liabilities.

+ References

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- Definition

Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

+ Details

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy.

+ References

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- Definition

Carrying value as of the balance sheet date of obligations and payables pertaining to claims incurred of a workers compensation nature. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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