Recent Accounting Pronouncements (Policies)	9 Months Ended
Sep. 29, 2017
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent Accounting Pronouncements	A new accounting standard that changed certain aspects of accounting for share-based payments became effective for the Company in the first quarter of 2017. Excess tax benefits on exercised stock options that were previously credited to equity now reduce the current income tax provision. For the quarter, the change in accounting for excess tax benefits decreased the current income tax provision and increased net earnings by $3.2 million, reduced the effective income tax rate by 3 percentage points, and increased diluted earnings per share by $0.06. For the year to date, the change in accounting for excess tax benefits decreased the current income tax provision and increased net earnings by $20.5 million, reduced the effective income tax rate by 7 percentage points, and increased diluted earnings per share by $0.36. Under the new standard, excess tax benefits are no longer reclassified out of cash flows from operating activities to financing activities in the Consolidated Statements of Cash Flows. We elected to apply the cash flow presentation requirements retrospectively to all periods presented, which resulted in a year-to-date increase in previously reported net cash provided by operating activities and a decrease in net cash provided by financing activities of $5.5 million for the nine months ended September 23, 2016. Also under the new standard, the Company elected to account for share-based grant forfeitures as they occur. The impact of the change in accounting for forfeitures was not significant, and was reflected in share-based compensation cost in the first quarter. In May 2014, the Financial Accounting Standards Board (FASB) issued a final standard on revenue from contracts with customers. The new standard sets forth a single comprehensive model for recognizing and reporting revenue. The new standard will become effective for the Company beginning with the first quarter of 2018, and the Company plans to adopt the accounting standard using the modified retrospective transition approach. The modified retrospective transition approach will recognize any changes from the beginning of the year of initial application through retained earnings with no restatement of comparative periods. We have established an implementation team and engaged a third-party consultant to assist with our assessment of the impact of the new revenue guidance on our operations, consolidated financial statements and related disclosures. To date, this assessment has included (1) utilizing questionnaires to assist with the identification of our revenue streams, (2) performing contract analyses for each revenue stream identified, (3) assessing the noted differences in recognition and measurement that may result from adopting this new standard, (4) performing detailed analyses of contracts with large customers, and (5) performing transaction level testing (based on our designed test plans) for consistency with contract provisions that affect revenue recognition. Based on the preliminary results of the evaluation, which is still in process, nothing has come to our attention that would indicate that adoption of the new standard will have a material impact on our consolidated financial statements. However, given our acquisition strategy, there may be additional revenue streams acquired prior to the adoption date. We currently believe the most significant potential change relates to whether certain project-based revenues will be recognized over time or at a point in time, although our technical analysis of potential impacts is still on-going. We also anticipate changes to the consolidated balance sheet related to accounts receivable, contract assets, and contract liabilities. We are in the process of evaluating and designing the necessary changes to our business processes, policies, systems and controls to support recognition and disclosure under the new standard. Further, we are continuing to assess what incremental disaggregated revenue disclosures will be required in our consolidated financial statements. The implementation team has reported these findings and the progress of the project to the Audit Committee of our Board of Directors. In March 2017, the FASB issued a final standard that changes the presentation of net periodic benefit cost related to defined benefit plans. The Company will adopt the standard when it becomes effective in fiscal 2018 and it will be applied retrospectively to all periods presented. Under the new standard, net periodic benefit costs are required to be disaggregated between service costs presented as operating expenses and other components of pension costs presented as non-operating expenses. The Company currently charges service costs to segment operations and includes other components of pension cost in unallocated corporate operating expenses. Under the new standard, unallocated corporate operating expenses will decrease, operating earnings will increase and other expense will increase by the amount of other (non-service) components of pension cost. There will be no impact on reported segment earnings, net earnings or earnings per share.

A new accounting standard that changed certain aspects of accounting for share-based payments became effective for the Company in the first quarter of 2017. Excess tax benefits on exercised stock options that were previously credited to equity now reduce the current income tax provision. For the quarter, the change in accounting for excess tax benefits decreased the current income tax provision and increased net earnings by $3.2 million, reduced the effective income tax rate by 3 percentage points, and increased diluted earnings per share by $0.06. For the year to date, the change in accounting for excess tax benefits decreased the current income tax provision and increased net earnings by $20.5 million, reduced the effective income tax rate by 7 percentage points, and increased diluted earnings per share by $0.36. Under the new standard, excess tax benefits are no longer reclassified out of cash flows from operating activities to financing activities in the Consolidated Statements of Cash Flows. We elected to apply the cash flow presentation requirements retrospectively to all periods presented, which resulted in a year-to-date increase in previously reported net cash provided by operating activities and a decrease in net cash provided by financing activities of $5.5 million for the nine months ended September 23, 2016. Also under the new standard, the Company elected to account for share-based grant forfeitures as they occur. The impact of the change in accounting for forfeitures was not significant, and was reflected in share-based compensation cost in the first quarter.

In May 2014, the Financial Accounting Standards Board (FASB) issued a final standard on revenue from contracts with customers. The new standard sets forth a single comprehensive model for recognizing and reporting revenue. The new standard will become effective for the Company beginning with the first quarter of 2018, and the Company plans to adopt the accounting standard using the modified retrospective transition approach. The modified retrospective transition approach will recognize any changes from the beginning of the year of initial application through retained earnings with no restatement of comparative periods.

We have established an implementation team and engaged a third-party consultant to assist with our assessment of the impact of the new revenue guidance on our operations, consolidated financial statements and related disclosures. To date, this assessment has included (1) utilizing questionnaires to assist with the identification of our revenue streams, (2) performing contract analyses for each revenue stream identified, (3) assessing the noted differences in recognition and measurement that may result from adopting this new standard, (4) performing detailed analyses of contracts with large customers, and (5) performing transaction level testing (based on our designed test plans) for consistency with contract provisions that affect revenue recognition. Based on the preliminary results of the evaluation, which is still in process, nothing has come to our attention that would indicate that adoption of the new standard will have a material impact on our consolidated financial statements. However, given our acquisition strategy, there may be additional revenue streams acquired prior to the adoption date. We currently believe the most significant potential change relates to whether certain project-based revenues will be recognized over time or at a point in time, although our technical analysis of potential impacts is still on-going. We also anticipate changes to the consolidated balance sheet related to accounts receivable, contract assets, and contract liabilities.

We are in the process of evaluating and designing the necessary changes to our business processes, policies, systems and controls to support recognition and disclosure under the new standard. Further, we are continuing to assess what incremental disaggregated revenue disclosures will be required in our consolidated financial statements. The implementation team has reported these findings and the progress of the project to the Audit Committee of our Board of Directors.

In March 2017, the FASB issued a final standard that changes the presentation of net periodic benefit cost related to defined benefit plans. The Company will adopt the standard when it becomes effective in fiscal 2018 and it will be applied retrospectively to all periods presented. Under the new standard, net periodic benefit costs are required to be disaggregated between service costs presented as operating expenses and other components of pension costs presented as non-operating expenses. The Company currently charges service costs to segment operations and includes other components of pension cost in unallocated corporate operating expenses. Under the new standard, unallocated corporate operating expenses will decrease, operating earnings will increase and other expense will increase by the amount of other (non-service) components of pension cost. There will be no impact on reported segment earnings, net earnings or earnings per share.