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Employee and Director Benefit Plans (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 29, 2018 | Dec. 30, 2017 | Dec. 31, 2016
Contributions to plan |  |  |
Contributions to defined contribution plans | $ 25,731 | $ 26,010 | $ 24,185
Net recognized gains (losses) of securities |  |  |
Gains (losses) on securities held in NQDC trust | (1,471) | 6,145 | 1,741
Defined Benefit Plan, Pension Plan with Project Benefit Obligation in Excess of Plan Assets [Abstract] |  |  |
Unfunded projected benefit obligation - defined benefit retirement plans | $ 7,990 | $ 6,976 | $ 6,164

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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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