Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Income Tax [Line Items]
Effective income tax rate		(14.10%)	(63.20%)	38.90%
Effective income tax rate with noncontrolling interest		(10.30%)	(70.30%)	41.80%
Federal corporate tax rate		21.00%	35.00%	35.00%
Tax Cuts and Jobs Act of 2017, estimated impact one-time benefit within income tax expense (benefit)			$ 69,000,000
Tax Cuts and Jobs Act of 2017, benefit partially offset and increase to valuation allowance			2,400,000
Tax Cuts and Jobs Act of 2017, change in tax rate income tax benefit net			66,600,000
Provisional tax benefit related to re-measurement of net deferred tax liability	$ 1,900,000
Uncertain tax positions		$ 3,100,000	2,400,000
Uncertain tax positions that would affect tax rate		3,100,000	2,400,000
Change in uncertain tax positions, expected material impact on consolidated financial statements		0
Valuation allowance for deferred tax assets		$ 5,899,000	$ 4,337,000
Earliest Tax Year [Member] | Internal Revenue Service (IRS) [Member]
Income Tax [Line Items]
Tax year open for examination		2002
State and Local Jurisdiction [Member]
Income Tax [Line Items]
Net operating losses		$ 93,500,000
Net operating loss carryforwards expiration ending year		2038
State and Local Jurisdiction [Member] | Earliest Tax Year [Member]
Income Tax [Line Items]
Tax year open for examination		1998
Federal Tax Authority [Member]
Income Tax [Line Items]
Net operating losses		$ 16,200,000