Partnership Capital Subject to Mandatory Redemption - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 26, 2020	Jun. 28, 2019	Jun. 26, 2020	Jun. 28, 2019	Dec. 31, 2019	Jan. 02, 2020	Jan. 02, 2019	Dec. 31, 2018	Jan. 12, 2018
Partners Capital Account [Line Items]
Period of loans made by Partnership to general partners			1 year		1 year
Outstanding amount of partner loans financed through the Partnership	$ 388	$ 399	$ 388	$ 399	$ 360			$ 332
Interest income from outstanding amount of general partner loan	$ 3	$ 5	$ 8	$ 11
Limited partnership's minimum annual return rate	7.50%	7.50%	7.50%	7.50%
Limited partnership's minimum return, value	$ 24	$ 23	$ 47	$ 47
2018 Limited Partnership Offering [Member]
Partners Capital Account [Line Items]
Limited partnership amount registered									$ 450
Limited partnership interests issued						$ 1	$ 380
Remaining limited partnership interests that may be issued	$ 69		$ 69