Supplemental Cash Flow Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash paid during the period for:
Interest	$ 71	$ 53	$ 61
Income taxes	98	71	30
Non-cash financing activities:
Stock compensation plans	15	10	12
Conversion of preferred stock into common stock		9	9
Dividends on preferred stock accrued not paid	$ 8	$ 8	$ 8
Per share preferred dividends not paid	$ 1.00	$ 1.00	$ 1.00