Income Taxes Income Taxes (Details Textuals) (USD $)	12 Months Ended
Dec. 30, 2014	Dec. 31, 2013	Dec. 25, 2012
Income Tax Contingency [Line Items]
Deferred Tax Assets, Valuation Allowance	$ 4,625,000	$ 3,173,000
Unrecognized Tax Benefits, net	6,100,000pnra_UnrecognizedTaxBenefitsNet	2,700,000pnra_UnrecognizedTaxBenefitsNet
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	300,000	(100,000)	200,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	$ 1,400,000	$ 900,000

The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date, net of federal benefits.

No definition available.

+ Details

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

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- Details

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- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

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- Definition

Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

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