Fair Value Accounting - Changes in the Fair Value of Level 3 Financial Liabilities (Details) $ in Millions	9 Months Ended
	Sep. 30, 2015 USD ($)
Summary of changes in Level 3 financial liabilities
Balance at beginning of period, liabilities	$ 189
Settlements	(9)
Revaluation	(49)
Balance at end of period, liabilities	131
Boddington Contingent Consideration
Summary of changes in Level 3 financial liabilities
Balance at beginning of period, liabilities	10
Balance at end of period, liabilities	10
Holt property royalty
Summary of changes in Level 3 financial liabilities
Balance at beginning of period, liabilities	179
Settlements	(9)
Revaluation	(49)
Balance at end of period, liabilities	$ 121