Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands		Sep. 29, 2017	Dec. 30, 2016
Assets
Money market securities	[1]	$ 5,265	$ 21,918
Total		131,826	128,940
Liabilities
Deferred compensation plan	[2]	56,479	53,617
Total		56,479	53,617
Fixed income securities
Assets
Fixed income available-for-sale securities	[3]	75,782	58,755
Fixed income trading securities held in deferred compensation plan	[4]	14,210	11,872
Equity securities
Assets
Equity trading securities held in deferred compensation plan	[4]	36,569	36,395
Fair Value, Inputs, Level 1
Assets
Money market securities	[1]	5,265	21,918
Total		56,044	70,185
Liabilities
Deferred compensation plan	[2]	56,479	53,617
Total		56,479	53,617
Fair Value, Inputs, Level 1 | Fixed income securities
Assets
Fixed income available-for-sale securities	[3]	0	0
Fixed income trading securities held in deferred compensation plan	[4]	14,210	11,872
Fair Value, Inputs, Level 1 | Equity securities
Assets
Equity trading securities held in deferred compensation plan	[4]	36,569	36,395
Fair Value, Inputs, Level 2
Assets
Money market securities	[1]	0	0
Total		75,782	58,755
Liabilities
Deferred compensation plan	[2]	0	0
Total		0	0
Fair Value, Inputs, Level 2 | Fixed income securities
Assets
Fixed income available-for-sale securities	[3]	75,782	58,755
Fixed income trading securities held in deferred compensation plan	[4]	0	0
Fair Value, Inputs, Level 2 | Equity securities
Assets
Equity trading securities held in deferred compensation plan	[4]	0	0
Fair Value, Inputs, Level 3
Assets
Money market securities	[1]	0	0
Total		0	0
Liabilities
Deferred compensation plan	[2]	0	0
Total		0	0
Fair Value, Inputs, Level 3 | Fixed income securities
Assets
Fixed income available-for-sale securities	[3]	0	0
Fixed income trading securities held in deferred compensation plan	[4]	0	0
Fair Value, Inputs, Level 3 | Equity securities
Assets
Equity trading securities held in deferred compensation plan	[4]	$ 0	$ 0

[1] Included in cash and cash equivalents on the Company’s unaudited condensed consolidated balance sheet.

[2] Included in accrued payroll and employee benefits and deferred compensation on the Company’s unaudited condensed consolidated balance sheet.

[3] Included in short-term investments on the Company’s unaudited condensed consolidated balance sheet.

[4] Included in prepaid expenses and other assets and deferred compensation plan assets on the Company’s unaudited condensed consolidated balance sheet.