Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Sep. 30, 2012
Current assets:
Cash and cash equivalents	$ 91	$ 120
Accounts and notes receivable, net of reserve for doubtful accounts of $5 and $5	619	687
Inventories:
Raw materials	143	131
Work in process	5	5
Finished goods	393	351
Other	46	46
Total inventories	587	533
Prepaid expenses and other current assets	82	71
Deferred income taxes	36	32
Total current assets	1,415	1,443
Property, plant and equipment, net	1,566	1,552
Goodwill	494	480
Equity affiliates	116	115
Intangible assets, net of accumulated amortization of $9 and $6	318	330
Assets held for rent	48	46
Notes receivable from sale of business	225	242
Deferred income taxes	98	94
Other assets	96	97
Total assets	4,376	4,399
Current liabilities:
Notes payable to banks	72	62
Accounts payable and accrued liabilities	504	606
Income taxes payable	27	59
Deferred income taxes	6	7
Current portion of long-term debt	188	185
Total current liabilities	797	919
Long-term debt	1,241	1,172
Deferred income taxes	54	55
Other liabilities	315	314
Commitments and contingencies (Note H)
Preferred stock:
Authorized: 2,000,000 shares of $1 par value Issued and Outstanding : None and none
Common stock:
Authorized: 200,000,000 shares of $1 par value Issued: 63,740,510 and 63,600,928 shares Outstanding: 63,994,075 and 63,347,362 shares	64	64
Less cost of 253,565 and 253,565 shares of common treasury stock	(8)	(8)
Additional paid-in capital	22	20
Retained earnings	1,660	1,653
Deferred employee benefits	(7)	(8)
Accumulated other comprehensive income	107	92
Total Cabot Corporation stockholders' equity	1,838	1,813
Noncontrolling interests	131	126
Total stockholders' equity	1,969	1,939
Total liabilities and stockholders' equity	$ 4,376	$ 4,399