General (Policies)	3 Months Ended
Jul. 27, 2019
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation In the opinion of management, the accompanying unaudited condensed consolidated financial statements contain all adjustments necessary to present fairly the financial position of Patterson Companies, Inc. (referred to herein as "Patterson" or in the first person notations "we," "our," and "us") as of July 27, 2019, and our results of operations and cash flows for the periods ended July 27, 2019 and July 28, 2018. Such adjustments are of a normal recurring nature. The results of operations for the three months ended July 27, 2019 are not necessarily indicative of the results to be expected for any other interim period or for the year ending April 25, 2020. These financial statements should be read in conjunction with the financial statements included in our 2019 Annual Report on Form 10-K filed on June 26, 2019. The unaudited condensed consolidated financial statements include the assets and liabilities of PDC Funding Company, LLC ("PDC Funding"), PDC Funding Company II, LLC ("PDC Funding II") and PDC Funding Company III, LLC ("PDC Funding III"), which are our wholly owned subsidiaries and separate legal entities formed under Minnesota law. PDC Funding and PDC Funding II are fully consolidated special purpose entities established to sell customer installment sale contracts to outside financial institutions in the normal course of their business. PDC Funding III is a fully consolidated special purpose entity established to sell certain receivables to unaffiliated financial institutions. The assets of PDC Funding, PDC Funding II and PDC Funding III would be available first and foremost to satisfy the claims of its creditors. There are no known creditors of PDC Funding, PDC Funding II or PDC Funding III.
Fiscal Year End	Fiscal Year End We operate with a 52-53 week accounting convention with our fiscal year ending on the last Saturday in April. The first quarter of fiscal 2020 and 2019 represents the 13 weeks ended July 27, 2019 and the 13 weeks ended July 28, 2018, respectively. Fiscal 2020 will include 52 weeks and fiscal 2019 included 52 weeks.
Comprehensive Income	Comprehensive Income Comprehensive income is computed as net income including certain other items that are recorded directly to stockholders’ equity. Significant items included in comprehensive income are foreign currency translation adjustments and the effective portion of cash flow hedges, net of tax. Foreign currency translation adjustments do not include a provision for income tax because earnings from foreign operations are considered to be indefinitely reinvested outside the U.S.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In February 2016, the FASB issued ASU No. 2016-02, "Leases (Topic 842)," which requires lessees to recognize assets and liabilities on the balance sheet for the rights and obligations created by most leases, as well as requires additional qualitative and quantitative disclosures. We adopted the new guidance in the first quarter of fiscal 2020 on a modified retrospective basis through a cumulative-effect adjustment to the beginning retained earnings in the period of adoption. We elected the transition package of practical expedients provided within the guidance, which eliminated the requirements to reassess lease identification, lease classification and initial direct costs for leases commenced before the effective date. We elected not to separate lease from non-lease components and to exclude short-term leases from our consolidated balance sheets. The impact of adopting the new lease standard primarily relates to the recognition of a lease right-of-use (“ROU”) asset and current and non-current lease liabilities on the condensed consolidated balance sheets. ROU assets represent our right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. Lease ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. As we cannot readily determine the rate implicit in most of our leases, we use an incremental borrowing rate determined by country of lease origin based on the anticipated lease term as determined at commencement date in determining the present value of lease payments. The new lease standard resulted in the recognition of lease ROU assets and liabilities of $86,046 and $88,333 as of April 28, 2019. In addition, $1,447 of net deferred gains on sale-leaseback transactions that existed as of April 27, 2019 were derecognized from our condensed consolidated balance sheet, with the offsetting impact being an adjustment to retained earnings as of April 28, 2019. The adoption of the guidance did not have a material impact on our condensed consolidated statements of income and other comprehensive income or condensed consolidated statements of cash flows as of the adoption date. Under the transition method of adoption, comparative information was not restated, but will continue to be reported under the standards in effect for those periods. In June 2016, the FASB issued ASU No. 2016-13, “Financial Instruments-Credit Losses (Topic 326),” which requires the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. We plan to adopt the new guidance in the first quarter of fiscal 2021. We are currently evaluating the impact of adopting this pronouncement. In February 2018, the FASB issued ASU No. 2018-02, "Income Statement-Reporting Comprehensive Income (Topic 220) Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income," which will allow a reclassification from accumulated other comprehensive income to retained earnings for the tax effects that are stranded in accumulated other comprehensive income as a result of tax reform. This standard also requires certain disclosures about stranded tax effects. We adopted ASU No. 2018-02 in the first quarter of fiscal 2020 and applied it in the period of adoption. As a result of the adoption, $2,707 was reclassified from accumulated other comprehensive loss to retained earnings in the first quarter of fiscal 2020.

General (Policies)

3 Months Ended

Jul. 27, 2019

In the opinion of management, the accompanying unaudited condensed consolidated financial statements contain all adjustments necessary to present fairly the financial position of Patterson Companies, Inc. (referred to herein as "Patterson" or in the first person notations "we," "our," and "us") as of July 27, 2019, and our results of operations and cash flows for the periods ended July 27, 2019 and July 28, 2018. Such adjustments are of a normal recurring nature. The results of operations for the three months ended July 27, 2019 are not necessarily indicative of the results to be expected for any other interim period or for the year ending April 25, 2020. These financial statements should be read in conjunction with the financial statements included in our 2019 Annual Report on Form 10-K filed on June 26, 2019.

The unaudited condensed consolidated financial statements include the assets and liabilities of PDC Funding Company, LLC ("PDC Funding"), PDC Funding Company II, LLC ("PDC Funding II") and PDC Funding Company III, LLC ("PDC Funding III"), which are our wholly owned subsidiaries and separate legal entities formed under Minnesota law. PDC Funding and PDC Funding II are fully consolidated special purpose entities established to sell customer installment sale contracts to outside financial institutions in the normal course of their business. PDC Funding III is a fully consolidated special purpose entity established to sell certain receivables to unaffiliated financial institutions. The assets of PDC Funding, PDC Funding II and PDC Funding III would be available first and foremost to satisfy the claims of its creditors. There are no known creditors of PDC Funding, PDC Funding II or PDC Funding III.

Fiscal Year End

We operate with a 52-53 week accounting convention with our fiscal year ending on the last Saturday in April. The first quarter of fiscal 2020 and 2019 represents the 13 weeks ended July 27, 2019 and the 13 weeks ended July 28, 2018, respectively. Fiscal 2020 will include 52 weeks and fiscal 2019 included 52 weeks.

Comprehensive Income

Comprehensive income is computed as net income including certain other items that are recorded directly to stockholders’ equity. Significant items included in comprehensive income are foreign currency translation adjustments and the effective portion of cash flow hedges, net of tax. Foreign currency translation adjustments do not include a provision for income tax because earnings from foreign operations are considered to be indefinitely reinvested outside the U.S.

Recently Issued Accounting Pronouncements

In February 2016, the FASB issued ASU No. 2016-02, "Leases (Topic 842)," which requires lessees to recognize assets and liabilities on the balance sheet for the rights and obligations created by most leases, as well as requires additional qualitative and quantitative disclosures. We adopted the new guidance in the first quarter of fiscal 2020 on a modified retrospective basis through a cumulative-effect adjustment to the beginning retained earnings in the period of adoption. We elected the transition package of practical expedients provided within the guidance, which eliminated the requirements to reassess lease identification, lease classification and initial direct costs for leases commenced before the effective date. We elected not to separate lease from non-lease components and to exclude short-term leases from our consolidated balance sheets.

The impact of adopting the new lease standard primarily relates to the recognition of a lease right-of-use (“ROU”) asset and current and non-current lease liabilities on the condensed consolidated balance sheets. ROU assets represent our right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. Lease ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. As we cannot readily determine the rate implicit in most of our leases, we use an incremental borrowing rate determined by country of lease origin based on the anticipated lease term as determined at commencement date in determining the present value of lease payments.

The new lease standard resulted in the recognition of lease ROU assets and liabilities of $86,046 and $88,333 as of April 28, 2019. In addition, $1,447 of net deferred gains on sale-leaseback transactions that existed as of April 27, 2019 were derecognized from our condensed consolidated balance sheet, with the offsetting impact being an adjustment to retained earnings as of April 28, 2019. The adoption of the guidance did not have a material impact on our condensed consolidated statements of income and other comprehensive income or condensed consolidated statements of cash flows as of the adoption date. Under the transition method of adoption, comparative information was not restated, but will continue to be reported under the standards in effect for those periods.

In June 2016, the FASB issued ASU No. 2016-13, “Financial Instruments-Credit Losses (Topic 326),” which requires the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. We plan to adopt the new guidance in the first quarter of fiscal 2021. We are currently evaluating the impact of adopting this pronouncement.

In February 2018, the FASB issued ASU No. 2018-02, "Income Statement-Reporting Comprehensive Income (Topic 220) Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income," which will allow a reclassification from accumulated other comprehensive income to retained earnings for the tax effects that are stranded in accumulated other comprehensive income as a result of tax reform. This standard also requires certain disclosures about stranded tax effects. We adopted ASU No. 2018-02 in the first quarter of fiscal 2020 and applied it in the period of adoption. As a result of the adoption, $2,707 was reclassified from accumulated other comprehensive loss to retained earnings in the first quarter of fiscal 2020.