SUPPLEMENTAL PARENT AND GUARANTOR CONDENSED CONSOLIDATING FINANCIAL STATEMENTS (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Sales
External									$ 3,505	$ 3,766	$ 3,672
Subsidiaries									0	0	0
Total sales	$ 853	$ 909	$ 864	$ 879	$ 933	$ 979	$ 954	$ 900	3,505	3,766	3,672
Cost of sales	(745)	(785)	(749)	(764)	(793)	(855)	(836)	(795)	(3,043)	(3,279)	(3,277)
GROSS MARGIN	108	124	115	115	140	124	118	105	462	487	395
Selling, general and administrative									(243)	(258)	(253)
Pension settlement losses									(59)	0	(109)
Restructuring costs	(1)	(9)	(3)	(3)	(7)		(2)	(1)	(16)	(10)	(23)
Goodwill impairment	(15)								(15)	0	0
Asset impairments									3	0	0
Other operating expense, net									(1)	(2)	(3)
OPERATING INCOME									128	217	7
Other income (expense), net									5	0	3
Gain on sale of equity investment									0	0	125
Equity in earnings of other ZF Meritor									0	190	0
Equity in earnings of affiliates									39	38	42
Interest income (expense), net									(105)	(130)	(126)
INCOME BEFORE INCOME TAXES									67	315	51
Provision for income taxes	18	(6)	(6)	(7)	0	(12)	(8)	(11)	(1)	(31)	(64)
Equity income from continuing operations of subsidiaries									0	0	0
INCOME (LOSS) FROM CONTINUING OPERATIONS									66	284	(13)
LOSS FROM DISCONTINUED OPERATIONS, net of tax									(1)	(30)	(7)
NET INCOME (LOSS)	(22)	14	43	30	4	234	3	13	65	254	(20)
Less: Net income attributable to noncontrolling interests									(1)	(5)	(2)
Net income (loss)	$ (21)	$ 13	$ 43	$ 29	$ 3	234	$ 1	$ 11	64	249	(22)
ZF Meritor LLC (Commercial Truck & Industrial)
Sales
Net income (loss)						$ 209
Other equity method investments
Sales
Equity in earnings of affiliates									39
Parent
Sales
External									0	0	0
Subsidiaries									0	0	0
Total sales									0	0	0
Cost of sales									(52)	(56)	(54)
GROSS MARGIN									(52)	(56)	(54)
Selling, general and administrative									(53)	(65)	(72)
Pension settlement losses									0		(73)
Restructuring costs									(2)	0	(3)
Goodwill impairment									0
Other operating expense, net									(2)	(1)	(2)
OPERATING INCOME									(109)	(122)	(204)
Other income (expense), net									36	35	39
Gain on sale of equity investment											0
Equity in earnings of other ZF Meritor										0
Equity in earnings of affiliates										0	0
Interest income (expense), net									(138)	(159)	(154)
INCOME BEFORE INCOME TAXES									(211)	(246)	(319)
Provision for income taxes									(2)	0	(1)
Equity income from continuing operations of subsidiaries									278	525	305
INCOME (LOSS) FROM CONTINUING OPERATIONS									65	279	(15)
LOSS FROM DISCONTINUED OPERATIONS, net of tax									(1)	(30)	(7)
NET INCOME (LOSS)									64	249	(22)
Less: Net income attributable to noncontrolling interests									0	0	0
Net income (loss)									64	249	(22)
Parent | Other equity method investments
Sales
Equity in earnings of affiliates									0
Guarantors
Sales
External									1,734	1,467	1,409
Subsidiaries									129	142	136
Total sales									1,863	1,609	1,545
Cost of sales									(1,579)	(1,343)	(1,339)
GROSS MARGIN									284	266	206
Selling, general and administrative									(118)	(102)	(87)
Pension settlement losses									0		0
Restructuring costs									(5)	(1)	(8)
Goodwill impairment									(15)
Other operating expense, net									(2)	(1)	(1)
OPERATING INCOME									144	162	110
Other income (expense), net									18	23	21
Gain on sale of equity investment											60
Equity in earnings of other ZF Meritor										190
Equity in earnings of affiliates										30	24
Interest income (expense), net									26	35	34
INCOME BEFORE INCOME TAXES									224	440	249
Provision for income taxes									2	(1)	(17)
Equity income from continuing operations of subsidiaries									38	71	57
INCOME (LOSS) FROM CONTINUING OPERATIONS									264	510	289
LOSS FROM DISCONTINUED OPERATIONS, net of tax									(2)	(31)	(8)
NET INCOME (LOSS)									262	479	281
Less: Net income attributable to noncontrolling interests									0	0	0
Net income (loss)									262	479	281
Guarantors | Other equity method investments
Sales
Equity in earnings of affiliates									36
Non- Guarantors
Sales
External									1,771	2,299	2,263
Subsidiaries									71	62	56
Total sales									1,842	2,361	2,319
Cost of sales									(1,612)	(2,084)	(2,076)
GROSS MARGIN									230	277	243
Selling, general and administrative									(72)	(91)	(94)
Pension settlement losses									(59)		(36)
Restructuring costs									(9)	(9)	(12)
Goodwill impairment									0
Other operating expense, net									3	0	0
OPERATING INCOME									93	177	101
Other income (expense), net									(49)	(58)	(57)
Gain on sale of equity investment											65
Equity in earnings of other ZF Meritor										0
Equity in earnings of affiliates										8	18
Interest income (expense), net									7	(6)	(6)
INCOME BEFORE INCOME TAXES									54	121	121
Provision for income taxes									(1)	(30)	(46)
Equity income from continuing operations of subsidiaries									0	0	0
INCOME (LOSS) FROM CONTINUING OPERATIONS									53	91	75
LOSS FROM DISCONTINUED OPERATIONS, net of tax									(3)	(12)	(237)
NET INCOME (LOSS)									50	79	(162)
Less: Net income attributable to noncontrolling interests									(1)	(5)	(2)
Net income (loss)									49	74	(164)
Non- Guarantors | Other equity method investments
Sales
Equity in earnings of affiliates									3
Elims
Sales
External									0	0	0
Subsidiaries									(200)	(204)	(192)
Total sales									(200)	(204)	(192)
Cost of sales									200	204	192
GROSS MARGIN									0	0	0
Selling, general and administrative									0	0	0
Pension settlement losses									0		0
Restructuring costs									0	0	0
Goodwill impairment									0
Other operating expense, net									0	0	0
OPERATING INCOME									0	0	0
Other income (expense), net									0	0	0
Gain on sale of equity investment											0
Equity in earnings of other ZF Meritor										0
Equity in earnings of affiliates										0	0
Interest income (expense), net									0	0	0
INCOME BEFORE INCOME TAXES									0	0	0
Provision for income taxes									0	0	0
Equity income from continuing operations of subsidiaries									(316)	(596)	(362)
INCOME (LOSS) FROM CONTINUING OPERATIONS									(316)	(596)	(362)
LOSS FROM DISCONTINUED OPERATIONS, net of tax									5	43	245
NET INCOME (LOSS)									(311)	(553)	(117)
Less: Net income attributable to noncontrolling interests									0	0	0
Net income (loss)									(311)	$ (553)	$ (117)
Elims | Other equity method investments
Sales
Equity in earnings of affiliates									$ 0