Basis of Presentation	6 Months Ended
Jul. 01, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
BASIS OF PRESENTATION	BASIS OF PRESENTATION The accompanying condensed consolidated financial statements are unaudited and have been prepared by Charles River Laboratories International, Inc. (the Company) in accordance with accounting principles generally accepted in the United States (U.S. GAAP) and pursuant to the rules and regulations of the Securities and Exchange Commission. The year-end condensed consolidated balance sheet data was derived from the Company’s audited consolidated financial statements, but does not include all disclosures required by U.S. GAAP. These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s Annual Report on Form 10-K for fiscal year 2016. The unaudited condensed consolidated financial statements, in the opinion of management, reflect all normal and recurring adjustments necessary for a fair statement of the Company’s financial position and results of operations. The Company has reclassified certain amounts in the unaudited condensed consolidated statements of cash flow for prior periods to conform to the current year presentation. See “Newly Adopted Accounting Pronouncements” below. Use of Estimates The preparation of unaudited condensed consolidated financial statements in accordance with U.S. GAAP requires that the Company make estimates and judgments that may affect the reported amounts of assets, liabilities, redeemable noncontrolling interest, revenues, expenses and related disclosure of contingent assets and liabilities. On an on-going basis, the Company evaluates its estimates, judgments and methodologies. The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities. Actual results may differ from these estimates under different assumptions or conditions. Changes in estimates are reflected in reported results in the period in which they become known. Consolidation The Company’s unaudited condensed consolidated financial statements reflect its financial statements and those of its subsidiaries in which the Company holds a controlling financial interest. For consolidated entities in which the Company owns or is exposed to less than 100% of the economics, the Company records net income (loss) attributable to noncontrolling interests in its consolidated statements of income equal to the percentage of the economic or ownership interest retained in such entities by the respective noncontrolling parties. Intercompany balances and transactions are eliminated in consolidation. The Company’s fiscal year is typically based on a 52-week year, with each quarter composed of 13 weeks ending on the last Saturday on, or closest to, March 31, June 30, September 30, and December 31. A 53^rd week was included in the fourth quarter of fiscal year 2016, which is occasionally necessary to align with a December 31 calendar year-end. Summary of Significant Accounting Policies The Company’s significant accounting policies are described in Note 1, “Description of Business and Summary of Significant Accounting Policies,” in the Company’s Annual Report on Form 10-K for fiscal year 2016. Newly Adopted Accounting Pronouncements In November 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2016-18, “Restricted Cash.” The standard addresses the classification and presentation of restricted cash and restricted cash equivalents within the statement of cash flows. The Company elected to early adopt this standard in fiscal year 2017 and applied the changes retrospectively to all prior periods presented in its unaudited condensed consolidated statements of cash flows. The Company historically excluded restricted cash balances, recorded in current and long-term other assets, from cash and cash equivalents within the unaudited consolidated statements of cash flows, reflecting transfers between cash, cash equivalents, and restricted cash as a cash flow classified within cash flows relating to operating activities. As a result of the adoption of this standard, the Company combined restricted cash balances of $2.3 million and $2.0 million as of June 25, 2016, and December 26, 2015, respectively, with cash and cash equivalents when reconciling the beginning and ending balances within the unaudited condensed consolidated statements of cash flows for the six months ended June 25, 2016. In August 2016, the FASB issued ASU 2016-15, “Classification of Certain Cash Receipts and Cash Payments.” The standard addresses the classification of certain transactions within the statement of cash flows, including cash payments for debt prepayment or debt extinguishment costs, contingent consideration payments made after a business combination, and distributions received from equity method investments. The Company elected to early adopt this standard in fiscal year 2017 and applied the changes retrospectively to all prior periods presented within its unaudited condensed consolidated statements of cash flows. The adoption of this standard had no impact within the unaudited condensed consolidated statement of cash flows for the six months ended June 25, 2016. In March 2016, the FASB issued ASU 2016-09, “Improvements to Employee Share-Based Payment Accounting.” The standard reduces complexity in several aspects of the accounting for employee share-based compensation, including the income tax consequences, classification of awards as either equity or liabilities, and classification within the statement of cash flows. The Company adopted this standard in fiscal year 2017, and applied the changes as required by each amendment to its unaudited condensed consolidated financial statements and related disclosures. Under ASU 2016-09, the Company adopted the amendment to recognize excess tax benefits and tax deficiencies in the consolidated statement of income on a prospective basis, to present excess tax benefits within operating activities within the unaudited condensed consolidated statements of cash flows on a retrospective basis, and elected to change its accounting policy to account for forfeitures as they occur on a modified retrospective basis. The adoption to recognize excess tax benefits and tax deficiencies within the unaudited condensed consolidated statements of income on a prospective basis could result in fluctuations in the effective tax rate period-over-period depending on how many awards vest and the volatility of the Company’s stock price. During the three months ended July 1, 2017, the impact to the provision for income taxes within the unaudited condensed consolidated statements of income was an excess tax benefit of $1.3 million. During the six months ended July 1, 2017, the impact on the provision for income taxes within the unaudited condensed consolidated statements of income was an excess tax benefit of $8.8 million. Further, for the three and six months ended July 1, 2017, the Company excluded the effect of windfall tax benefits from the hypothetical proceeds used to calculate the repurchase of shares under the treasury stock method for the calculation of diluted earnings per share. The adoption of the amendment to present excess tax benefits within operating activities within the unaudited condensed consolidated statements of cash flows on a retrospective basis resulted in the reclassification of a cash inflow of $9.1 million from cash provided by financing activities to cash provided by operating activities for the six months ended June 25, 2016. The Company had previously classified cash paid for tax withholding purposes as a financing activity within the unaudited condensed consolidated statements of cash flows; therefore, there was no change related to this requirement under the amendment. The Company’s election to change its accounting policy to account for forfeitures when they occur on a modified retrospective basis resulted in an immaterial impact on its unaudited condensed consolidated financial statements and related disclosures. Newly Issued Accounting Pronouncements In March 2017, the FASB issued ASU 2017-07, “Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost.” The standard requires an employer to disaggregate the service cost component from the other components of net benefit cost and provides explicit guidance on the presentation of the service cost component and the other components of net benefit cost in the statements of income. The ASU is effective for annual periods beginning after December 15, 2017, including interim periods within those fiscal years, and should be applied retrospectively for the presentation of the service cost component and the other components of net periodic pension cost in the statements of income. Early adoption is permitted within the first interim period of the fiscal year. The Company is still evaluating the impact this standard will have on its consolidated financial statements and related disclosures. In January 2017, the FASB issued ASU 2017-04, “Simplifying the Test for Goodwill Impairment.” The standard simplifies the accounting for goodwill impairment by removing Step 2 of the goodwill impairment test, which requires a hypothetical purchase price allocation. This standard is effective for annual or interim goodwill impairment tests in fiscal years beginning after December 15, 2019, and will be applied on a prospective basis. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company is still evaluating the impact this standard will have on its consolidated financial statements and related disclosures. In January 2017, the FASB issued ASU 2017-01, “Clarifying the Definition of a Business.” The standard clarifies the definition of a business by adding guidance to assist entities in evaluating whether transactions should be accounted for as acquisitions of assets or businesses. This standard is effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption is permitted for certain transactions. The Company is still evaluating the impact this standard will have on its consolidated financial statements and related disclosures. In October 2016, the FASB issued ASU 2016-16, “Intra-Entity Transfers of Assets Other Than Inventory.” The standard requires the immediate recognition of tax effects for an intra-entity asset transfer other than inventory. This standard is effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption is permitted. The adoption of this standard is not expected to have a material impact on the Company’s consolidated financial statements and related disclosures. In February 2016, the FASB issued ASU 2016-02, “Leases.” The standard established the principles that lessees and lessors will apply to report useful information to users of financial statements about the amount, timing and uncertainty of cash flows arising from a lease. This standard is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption is permitted. The Company is still evaluating the full impact this standard will have on its consolidated financial statements and related disclosures, but expects to recognize substantially all of its leases on the balance sheet by recording a right-to-use asset and a corresponding lease liability. In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers.” The standard, including subsequently issued amendments, will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective and permits the use of either a modified retrospective or cumulative effect transition method. The standard will require an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The standard will be effective for annual and interim periods beginning after December 15, 2017. The Company formed an implementation team during fiscal year 2016 to oversee adoption of the new standard. The implementation team has completed its initial assessment of the new standard, including a detailed review of the Company’s contract portfolio, revenue streams to identify potential differences in accounting as a result of the new standard, and selected the modified retrospective transition method. The Company continues to assess the impact on the existing revenue accounting policies, newly required financial statement disclosures, and executing on the project plan. Currently, the Company is finalizing contract reviews, working through anticipated changes to systems and business processes, and internal controls to support the adoption of the new standard.

BASIS OF PRESENTATION

The accompanying condensed consolidated financial statements are unaudited and have been prepared by Charles River Laboratories International, Inc. (the Company) in accordance with accounting principles generally accepted in the United States (U.S. GAAP) and pursuant to the rules and regulations of the Securities and Exchange Commission. The year-end condensed consolidated balance sheet data was derived from the Company’s audited consolidated financial statements, but does not include all disclosures required by U.S. GAAP. These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s Annual Report on Form 10-K for fiscal year 2016. The unaudited condensed consolidated financial statements, in the opinion of management, reflect all normal and recurring adjustments necessary for a fair statement of the Company’s financial position and results of operations.

The Company has reclassified certain amounts in the unaudited condensed consolidated statements of cash flow for prior periods to conform to the current year presentation. See “Newly Adopted Accounting Pronouncements” below.

Use of Estimates

The preparation of unaudited condensed consolidated financial statements in accordance with U.S. GAAP requires that the Company make estimates and judgments that may affect the reported amounts of assets, liabilities, redeemable noncontrolling interest, revenues, expenses and related disclosure of contingent assets and liabilities. On an on-going basis, the Company evaluates its estimates, judgments and methodologies. The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities. Actual results may differ from these estimates under different assumptions or conditions. Changes in estimates are reflected in reported results in the period in which they become known.

Consolidation

The Company’s unaudited condensed consolidated financial statements reflect its financial statements and those of its subsidiaries in which the Company holds a controlling financial interest. For consolidated entities in which the Company owns or is exposed to less than 100% of the economics, the Company records net income (loss) attributable to noncontrolling interests in its consolidated statements of income equal to the percentage of the economic or ownership interest retained in such entities by the respective noncontrolling parties. Intercompany balances and transactions are eliminated in consolidation.

The Company’s fiscal year is typically based on a 52-week year, with each quarter composed of 13 weeks ending on the last Saturday on, or closest to, March 31, June 30, September 30, and December 31. A 53^rd week was included in the fourth quarter of fiscal year 2016, which is occasionally necessary to align with a December 31 calendar year-end.

Summary of Significant Accounting Policies

The Company’s significant accounting policies are described in Note 1, “Description of Business and Summary of Significant Accounting Policies,” in the Company’s Annual Report on Form 10-K for fiscal year 2016.

Newly Adopted Accounting Pronouncements

In November 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2016-18, “Restricted Cash.” The standard addresses the classification and presentation of restricted cash and restricted cash equivalents within the statement of cash flows. The Company elected to early adopt this standard in fiscal year 2017 and applied the changes retrospectively to all prior periods presented in its unaudited condensed consolidated statements of cash flows.

The Company historically excluded restricted cash balances, recorded in current and long-term other assets, from cash and cash equivalents within the unaudited consolidated statements of cash flows, reflecting transfers between cash, cash equivalents, and restricted cash as a cash flow classified within cash flows relating to operating activities. As a result of the adoption of this standard, the Company combined restricted cash balances of $2.3 million and $2.0 million as of June 25, 2016, and December 26, 2015, respectively, with cash and cash equivalents when reconciling the beginning and ending balances within the unaudited condensed consolidated statements of cash flows for the six months ended June 25, 2016.

In August 2016, the FASB issued ASU 2016-15, “Classification of Certain Cash Receipts and Cash Payments.” The standard addresses the classification of certain transactions within the statement of cash flows, including cash payments for debt prepayment or debt extinguishment costs, contingent consideration payments made after a business combination, and distributions received from equity method investments. The Company elected to early adopt this standard in fiscal year 2017 and applied the changes retrospectively to all prior periods presented within its unaudited condensed consolidated statements of cash flows. The adoption of this standard had no impact within the unaudited condensed consolidated statement of cash flows for the six months ended June 25, 2016.

In March 2016, the FASB issued ASU 2016-09, “Improvements to Employee Share-Based Payment Accounting.” The standard reduces complexity in several aspects of the accounting for employee share-based compensation, including the income tax consequences, classification of awards as either equity or liabilities, and classification within the statement of cash flows. The Company adopted this standard in fiscal year 2017, and applied the changes as required by each amendment to its unaudited condensed consolidated financial statements and related disclosures.

Under ASU 2016-09, the Company adopted the amendment to recognize excess tax benefits and tax deficiencies in the consolidated statement of income on a prospective basis, to present excess tax benefits within operating activities within the unaudited condensed consolidated statements of cash flows on a retrospective basis, and elected to change its accounting policy to account for forfeitures as they occur on a modified retrospective basis.

The adoption to recognize excess tax benefits and tax deficiencies within the unaudited condensed consolidated statements of income on a prospective basis could result in fluctuations in the effective tax rate period-over-period depending on how many awards vest and the volatility of the Company’s stock price. During the three months ended July 1, 2017, the impact to the provision for income taxes within the unaudited condensed consolidated statements of income was an excess tax benefit of $1.3 million. During the six months ended July 1, 2017, the impact on the provision for income taxes within the unaudited condensed consolidated statements of income was an excess tax benefit of $8.8 million. Further, for the three and six months ended July 1, 2017, the Company excluded the effect of windfall tax benefits from the hypothetical proceeds used to calculate the repurchase of shares under the treasury stock method for the calculation of diluted earnings per share.

The adoption of the amendment to present excess tax benefits within operating activities within the unaudited condensed consolidated statements of cash flows on a retrospective basis resulted in the reclassification of a cash inflow of $9.1 million from cash provided by financing activities to cash provided by operating activities for the six months ended June 25, 2016. The Company had previously classified cash paid for tax withholding purposes as a financing activity within the unaudited condensed consolidated statements of cash flows; therefore, there was no change related to this requirement under the amendment.

The Company’s election to change its accounting policy to account for forfeitures when they occur on a modified retrospective basis resulted in an immaterial impact on its unaudited condensed consolidated financial statements and related disclosures.

Newly Issued Accounting Pronouncements

In March 2017, the FASB issued ASU 2017-07, “Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost.” The standard requires an employer to disaggregate the service cost component from the other components of net benefit cost and provides explicit guidance on the presentation of the service cost component and the other components of net benefit cost in the statements of income. The ASU is effective for annual periods beginning after December 15, 2017, including interim periods within those fiscal years, and should be applied retrospectively for the presentation of the service cost component and the other components of net periodic pension cost in the statements of income. Early adoption is permitted within the first interim period of the fiscal year. The Company is still evaluating the impact this standard will have on its consolidated financial statements and related disclosures.

In January 2017, the FASB issued ASU 2017-04, “Simplifying the Test for Goodwill Impairment.” The standard simplifies the accounting for goodwill impairment by removing Step 2 of the goodwill impairment test, which requires a hypothetical purchase price allocation. This standard is effective for annual or interim goodwill impairment tests in fiscal years beginning after December 15, 2019, and will be applied on a prospective basis. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company is still evaluating the impact this standard will have on its consolidated financial statements and related disclosures.

In January 2017, the FASB issued ASU 2017-01, “Clarifying the Definition of a Business.” The standard clarifies the definition of a business by adding guidance to assist entities in evaluating whether transactions should be accounted for as acquisitions of assets or businesses. This standard is effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption is permitted for certain transactions. The Company is still evaluating the impact this standard will have on its consolidated financial statements and related disclosures.

In October 2016, the FASB issued ASU 2016-16, “Intra-Entity Transfers of Assets Other Than Inventory.” The standard requires the immediate recognition of tax effects for an intra-entity asset transfer other than inventory. This standard is effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption is permitted. The adoption of this standard is not expected to have a material impact on the Company’s consolidated financial statements and related disclosures.

In February 2016, the FASB issued ASU 2016-02, “Leases.” The standard established the principles that lessees and lessors will apply to report useful information to users of financial statements about the amount, timing and uncertainty of cash flows arising from a lease. This standard is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption is permitted. The Company is still evaluating the full impact this standard will have on its consolidated financial statements and related disclosures, but expects to recognize substantially all of its leases on the balance sheet by recording a right-to-use asset and a corresponding lease liability.

In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers.” The standard, including subsequently issued amendments, will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective and permits the use of either a modified retrospective or cumulative effect transition method. The standard will require an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The standard will be effective for annual and interim periods beginning after December 15, 2017. The Company formed an implementation team during fiscal year 2016 to oversee adoption of the new standard. The implementation team has completed its initial assessment of the new standard, including a detailed review of the Company’s contract portfolio, revenue streams to identify potential differences in accounting as a result of the new standard, and selected the modified retrospective transition method. The Company continues to assess the impact on the existing revenue accounting policies, newly required financial statement disclosures, and executing on the project plan. Currently, the Company is finalizing contract reviews, working through anticipated changes to systems and business processes, and internal controls to support the adoption of the new standard.