Partnership Capital - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 29, 2019	Mar. 30, 2018	Dec. 31, 2018	Jan. 12, 2018	Dec. 31, 2017
Partners Capital Account [Line Items]
Period of loans made by Partnership to general partners	1 year
Outstanding amount of partner loans financed through the Partnership	$ 422	$ 381	$ 332		$ 297
Interest income from outstanding amount of general partner loan	$ 6	$ 4
Limited partnership's minimum annual payment rate	7.50%	7.50%
Limited partnership's minimum return, value	$ 24	$ 17
2018 Limited Partnership Offering [Member]
Partners Capital Account [Line Items]
Limited partnership amount registered				$ 450
Limited partnership interests issued	380
Remaining limited partnership interests that may be issued	$ 70