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, 2017	$ 2,795	$ 956	$ 499	$ 1,340
Reserve for anticipated withdrawals at Dec. 31, 2017	(290)	(66)	(36)	(188)
Partnership capital subject to mandatory redemption, net of reserve for anticipated withdrawals at Dec. 31, 2017	2,505	890	463	1,152
Partnership loans outstanding at beginning of year at Dec. 31, 2017	297	0	3	294
Total partnership capital, including capital financed with partnership loans, net of reserve for anticipated withdrawals at Dec. 31, 2017	2,802	890	466	1,446
Issuance of partnership interests	225	4	51	170
Redemption of partnership interests	(159)	(2)	(6)	(151)
Income allocated to partners	233	27	30	176
Distributions	(12)	0	(1)	(11)
Total partnership capital, including capital financed with partnership loans at Mar. 30, 2018	3,089	919	540	1,630
Issuance of partnership interests	3	1	1	1
Redemption of partnership interests	(14)	(2)	(4)	(8)
Income allocated to partners	240	28	31	181
Distributions	(283)	(6)	(51)	(226)
Total partnership capital, including capital financed with partnership loans at Jun. 29, 2018	3,035	940	517	1,578
Partnership loans outstanding, reduction to arrive at Partnership Capital at Jun. 29, 2018	(353)	0	(2)	(351)
TOTAL PARTNERSHIP CAPITAL SUBJECT TO MANDATORY REDEMPTION at Jun. 29, 2018	2,682	940	515	1,227
Reserve for anticipated withdrawals at Jun. 29, 2018	(128)	(49)	(9)	(70)
Partnership capital subject to mandatory redemption, net of reserve for anticipated withdrawals at Jun. 29, 2018	2,554	891	506	1,157
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
Partnership loans outstanding, reduction to arrive at Partnership Capital at Jun. 28, 2019	(399)	0	(4)	(395)
TOTAL PARTNERSHIP CAPITAL SUBJECT TO MANDATORY REDEMPTION at Jun. 28, 2019	3,181	1,333	534	1,314
Reserve for anticipated withdrawals at Jun. 28, 2019	(169)	(75)	(11)	(83)
Partnership capital subject to mandatory redemption, net of reserve for anticipated withdrawals at Jun. 28, 2019	$ 3,012	$ 1,258	$ 523	$ 1,231