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Retirement Plans (Narrative) (Details) - USD ($) | 3 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Dec. 31, 2015 | Oct. 02, 2016 | Sep. 30, 2018 | Oct. 01, 2017 | Oct. 02, 2016 | Jan. 01, 2017
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Minimum Required Contribution For Retirement Plans |  |  |  |  |  | $ 0
Decrease in earnings before income taxes due to quarter percentage point decrease in discount rate |  |  | $ 500,000 |  |  |
Decrease in earnings before income taxes due to quarter percentage point decrease in long-term rate of return |  |  | $ 1,100,000 |  |  |
Qualified Defined Contribution Plan [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Defined Benefit Plans, General Information |  |  | P21Y |  |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay | 4.00% | 4.00% |  |  |  |
Defined Contribution Plan, Cost |  |  | $ 2,200,000 | $ 1,900,000 | $ 3,200,000 |
Defined Contribution Plan, Employer Matching Contribution, Percent of Match | 50.00% | 100.00% |  |  |  |
Non-Qualified Deferred Compensation Plan [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Period of years in executive position |  |  | 10 years |  |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay | 3.00% |  | 4.00% |  |  |
Defined Contribution Plan, Cost |  |  | $ 200,000 | $ 500,000 | $ 300,000 |
Defined Contribution Plan, Employer Matching Contribution, Percent of Match | 100.00% |  |  |  |  |
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent |  |  | 50.00% |  |  |
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent of Bonus |  |  | 85.00% |  |  |
Vesting percentage of participant's right to company contribution |  |  | 25.00% |  |  |
Maximum [Member] | Non-Qualified Deferred Compensation Plan [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay |  | 4.00% |  |  |  |

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- Definition Defined benefit plan effect of quarter percentage point decrease in discount rate on earnings before tax. + References No definition available. + Details
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- Definition Defined benefit plan effect of quarter percentage point decrease in long term rate of return on earnings before tax. + References No definition available. + Details
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- Definition Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent of Bonus + References No definition available. + Details
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- Definition Defined contribution plan, minimum age of eligible employees. + References No definition available. + Details
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- Definition Minimum required contribution for retirement plans + References No definition available. + Details
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- Definition Period of years in executive position + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
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- Definition Percentage employer matches of the employee's percentage contribution matched. + References No definition available. + Details
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- Definition Percentage of employer's matching contributions to a defined contribution plan that vests in a given year. + References No definition available. + Details
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- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
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- Details
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