EQUITY, ROYALTY AND INTEREST INCOME FROM INVESTEES (Details) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 25, 2011	Sep. 26, 2010	Sep. 25, 2011	Sep. 26, 2010
Equity, royalty and interest income from investees:
Cummins share of net income	$ 94	$ 81	$ 284	$ 239
Royalty and interest income	8	7	31	22
Equity, royalty and interest income from investees	102	88	315	261
Distribution - North American distributors
Equity, royalty and interest income from investees:
Cummins share of net income	35	26	100	72
Distribution - Komatsu Cummins Chile, Ltda.
Equity, royalty and interest income from investees:
Cummins share of net income	6	5	16	11
Distribution - All other distributors
Equity, royalty and interest income from investees:
Cummins share of net income	1		3	2
Manufacturing - Chongqing Cummins Engine Company, Ltd.
Equity, royalty and interest income from investees:
Cummins share of net income	20	12	51	35
Manufacturing - Dongfeng Cummins Engine Company, Ltd.
Equity, royalty and interest income from investees:
Cummins share of net income	15	24	64	76
Manufacturing - Shanghai Fleetguard Filter Co. Ltd.
Equity, royalty and interest income from investees:
Cummins share of net income	4	3	12	9
Manufacturing - Cummins Westport, Inc.
Equity, royalty and interest income from investees:
Cummins share of net income	4	2	8	7
Manufacturing - Tata Cummins Ltd.
Equity, royalty and interest income from investees:
Cummins share of net income	2	4	9	11
Manufacturing - Valvoline Cummins, Ltd.
Equity, royalty and interest income from investees:
Cummins share of net income	2	2	6	7
Manufacturing - Komatsu manufacturing alliances
Equity, royalty and interest income from investees:
Cummins share of net income		2	1	7
Manufacturing - Beijing Foton Cummins Engine Co., Ltd.
Equity, royalty and interest income from investees:
Cummins share of net income	(2)	(6)	(5)	(12)
Manufacturing - All other manufacturers
Equity, royalty and interest income from investees:
Cummins share of net income	$ 7	$ 7	$ 19	$ 14