Employee and Director Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Contributions to plan
Contributions to defined contribution plans	$ 26,010	$ 24,185	$ 22,337
Net recognized gains (losses) of trading securities
Trading securities	6,145	1,741	(369)
Defined Benefit Plan, Plan with Benefit Obligation in Excess of Plan Assets [Abstract]
Unfunded projected benefit obligation - defined benefit retirement plans	6,976	6,164	6,131
Expense related to defined benefit plans
Expense related to defined benefit plans	$ 1,214	$ 670	$ 1,359

Contributions to plan.

No definition available.

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- Definition

Gains (losses) on trading securities in the non-qualified deferred compensation trust.

+ References

No definition available.

+ Details

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- Definition

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- References

No definition available.

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- References

No definition available.

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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

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- References

No definition available.

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