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Stock Option Plans - Additional information (Detail) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended
	Mar. 14, 2019	Mar. 15, 2018	Mar. 31, 2019	Mar. 31, 2018
Stock Option Plans [Line Items]
Maximum number of shares available			399,900	420,200
Compensation expense related to stock option grants			$ 3.6	$ 4.8
Total intrinsic value of options exercised			27.6	$ 29.3
Total unrecognized compensation cost related to nonvested options			$ 40.5
Weighted average period, years			4 years
Long Term Incentive Plan [Member]
Stock Option Plans [Line Items]
Maximum number of shares available			2,800,000
Shares available for grant			13,000,000
2017 Long Term Incentive Plan [Member]
Stock Option Plans [Line Items]
Number of years options expire from date of grant			7 years
Officer and Key Employees [Member] | 2017 Long Term Incentive Plan [Member]
Stock Option Plans [Line Items]
Shares available for grant	1,283,300	1,261,000
Stock options granted, exercise percentage, on the third anniversary date of the grant	34.00%	34.00%
Stock options granted, exercise percentage, on the fourth anniversary date of the grant	33.00%	33.00%
Stock options granted, exercise percentage, on the fifth anniversary date of the grant	33.00%	33.00%
Maximum [Member] | Long Term Incentive Plan [Member]
Stock Option Plans [Line Items]
Maximum period for the exercise of stock options, years			7 years	7 years
Minimum [Member] | Long Term Incentive Plan [Member]
Stock Option Plans [Line Items]
Minimum exercise price of stock options, percent of fair market value of a share of common stock on the date of grant			100.00%
Minimum [Member] | 2017 Long Term Incentive Plan [Member]
Stock Option Plans [Line Items]
Period of service from grant date stock options awarded not subject to forfeiture			2 years	2 years
Minimum [Member] | Executive Officer [Member] | 2017 Long Term Incentive Plan [Member]
Stock Option Plans [Line Items]
Minimum age of employee with not subject to award forfeiture on condition compliance			55 years	55 years
Black-Scholes Option Pricing Model [Member]
Stock Option Plans [Line Items]
Weighted average fair value per option for all options			$ 10.71	$ 9.27

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