Debt (Details 2) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Scheduled maturities of debt
2013	$ 2,738
2014	269
2015	482
2016	1,597
2017	1,211
Thereafter	7,807
Total debt, excluding unamortized discounts, premiums and fair value adjustments	14,104
Total unamortized discounts, premiums and fair value adjustments	13
Total debt	14,117	13,536
Transocean Ltd. and Subsidiaries
Scheduled maturities of debt
2013	2,710
2014	240
2015	451
2016	1,535
2017	1,175
Thereafter	7,788
Total debt, excluding unamortized discounts, premiums and fair value adjustments	13,899
Total unamortized discounts, premiums and fair value adjustments	13
Total debt	13,912	12,698
Consolidated variable interest entities
Scheduled maturities of debt
2013	28
2014	29
2015	31
2016	62
2017	36
Thereafter	19
Total debt, excluding unamortized discounts, premiums and fair value adjustments	205
Total debt	$ 205	$ 838

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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The amount of debt discount (net of debt premium) that was originally recognized at the issuance of the instrument that has yet to be amortized.

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