Summary of Significant Accounting Policies and Change in Accounting Principles (Policies)

6 Months Ended

Dec. 27, 2014

Accounting Policies [Abstract]

Basis of Accounting, Policy [Policy Text Block]

Basis of Presentation

The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles ("GAAP") for interim financial information and with the instructions to Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. The unaudited condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and footnotes included in Perrigo Company plc's Annual Report on Form 10-K for the year ended June 28, 2014. In the opinion of management, all adjustments (consisting of normal recurring accruals and other adjustments) considered necessary for a fair presentation have been included.

The Company’s sales of OTC pharmaceutical products are subject to the seasonal demands for cough/cold/flu and allergy products and consumer dynamics in the retail environments in which our customers operate. In addition, the Company's animal health products are subject to the seasonal demand for flea and tick products, which typically peaks during the warmer weather months. Accordingly, operating results for the three and six months endedDecember 27, 2014 are not necessarily indicative of the results that may be expected for a full fiscal year.

Change in Fiscal Year [Text Block]

Change in Fiscal Year

On December 18, 2014, the Board of Directors of the Company determined that the Company's fiscal year-end shall begin on January 1 and end on December 31 of each year, starting on January 1, 2016. The Company's current fiscal year will end on June 27, 2015, followed by a transition period from June 28, 2015 to December 31, 2015. The Company plans to disclose the results of the transition period on a Form 10-KT transition report.

Consolidation, Policy [Policy Text Block]

Principles of Consolidation

The condensed consolidated financial statements include the accounts of the Company and all majority-owned subsidiaries. All intercompany transactions and balances have been eliminated in consolidation.

New Accounting Pronouncements and Changes in Accounting Principles [Text Block]

Recently Adopted Accounting Standards

In July 2013, the Financial Accounting Standards Board issued Accounting Standards Update 2013-11, "Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists" ("ASU 2013-11"). The amendments in ASU 2013-11 provide guidance on the financial statement presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists. The Company prospectively adopted this guidance in fiscal 2015, and presented $90.2 million as a reclassification from Non-current deferred income taxes to Other non-current liabilities upon adoption.