Consolidated Statements of Changes in Partnership Capital Subject to Mandatory Redemption - USD ($) $ in Millions	Total	Limited Partnership Capital [Member]	Subordinated Limited Partnership Capital [Member]	General Partnership Capital [Member]
TOTAL PARTNERSHIP CAPITAL SUBJECT TO MANDATORY REDEMPTION at Dec. 31, 2018	$ 2,855	$ 956	$ 545	$ 1,354
Reserve for anticipated withdrawals at Dec. 31, 2018	(348)	(72)	(41)	(235)
Partnership capital subject to mandatory redemption, net of reserve for anticipated withdrawals at Dec. 31, 2018	2,507	884	504	1,119
Partnership loans outstanding at beginning of year at Dec. 31, 2018	332	0	4	328
Total partnership capital, including capital financed with partnership loans, net of reserve for anticipated withdrawals at Dec. 31, 2018	2,839	884	508	1,447
Issuance of partnership interests	593	380	51	162
Redemption of partnership interests	(71)	(3)	(31)	(37)
Income allocated to partners	241	37	29	175
Distributions	(6)	0	0	(6)
Total partnership capital, including capital financed with partnership loans at Mar. 29, 2019	3,596	1,298	557	1,741
Issuance of partnership interests	1	0	0	1
Redemption of partnership interests	(4)	(3)	(1)	0
Income allocated to partners	285	43	34	208
Distributions	(298)	(5)	(52)	(241)
Total partnership capital, including capital financed with partnership loans at Jun. 28, 2019	3,580	1,333	538	1,709
Issuance of partnership interests	2	0	2	0
Redemption of partnership interests	(38)	(5)	(2)	(31)
Income allocated to partners	281	43	34	204
Distributions	(202)	(1)	(35)	(166)
Total partnership capital, including capital financed with partnership loans at Sep. 27, 2019	3,623	1,370	537	1,716
Partnership loans outstanding, reduction to arrive at Partnership Capital at Sep. 27, 2019	(373)	0	(4)	(369)
TOTAL PARTNERSHIP CAPITAL SUBJECT TO MANDATORY REDEMPTION at Sep. 27, 2019	3,250	1,370	533	1,347
Reserve for anticipated withdrawals at Sep. 27, 2019	(221)	(117)	(10)	(94)
Partnership capital subject to mandatory redemption, net of reserve for anticipated withdrawals at Sep. 27, 2019	3,029	1,253	523	1,253
TOTAL PARTNERSHIP CAPITAL SUBJECT TO MANDATORY REDEMPTION at Dec. 31, 2019	3,364	1,359	566	1,439
Reserve for anticipated withdrawals at Dec. 31, 2019	(407)	(110)	(43)	(254)
Partnership capital subject to mandatory redemption, net of reserve for anticipated withdrawals at Dec. 31, 2019	2,957	1,249	523	1,185
Partnership loans outstanding at beginning of year at Dec. 31, 2019	360	0	4	356
Total partnership capital, including capital financed with partnership loans, net of reserve for anticipated withdrawals at Dec. 31, 2019	3,317	1,249	527	1,541
Issuance of partnership interests	213	1	49	163
Redemption of partnership interests	(81)	(3)	(35)	(43)
Income allocated to partners	303	50	35	218
Distributions	(5)	0	0	(5)
Total partnership capital, including capital financed with partnership loans at Mar. 27, 2020	3,747	1,297	576	1,874
Issuance of partnership interests	0	0	0	0
Redemption of partnership interests	(6)	(3)	(1)	(2)
Income allocated to partners	288	42	34	212
Distributions	(349)	(14)	(58)	(277)
Total partnership capital, including capital financed with partnership loans at Jun. 26, 2020	3,680	1,322	551	1,807
Issuance of partnership interests	0	0	0	0
Redemption of partnership interests	(13)	(4)	(1)	(8)
Income allocated to partners	316	45	37	234
Distributions	(208)	0	(35)	(173)
Total partnership capital, including capital financed with partnership loans at Sep. 25, 2020	3,775	1,363	552	1,860
Partnership loans outstanding, reduction to arrive at Partnership Capital at Sep. 25, 2020	(363)	0	(1)	(362)
TOTAL PARTNERSHIP CAPITAL SUBJECT TO MANDATORY REDEMPTION at Sep. 25, 2020	3,412	1,363	551	1,498
Reserve for anticipated withdrawals at Sep. 25, 2020	(254)	(123)	(13)	(118)
Partnership capital subject to mandatory redemption, net of reserve for anticipated withdrawals at Sep. 25, 2020	$ 3,158	$ 1,240	$ 538	$ 1,380