Partners Capital Subsequent Events (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended		0 Months Ended		1 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Jul. 18, 2012 Dividend Declared [Member]	Jul. 18, 2012 Issuance of Equity [Member]	Jul. 26, 2012 Issuance of Equity [Member]
Subsequent Event [Line Items]
Issuance of common units for the settlement of sales (in shares)							269,501
Proceeds on sales of units	$ 110		$ 1,114	$ 813			$ 22
Per unit cash distribution declared (usd per share)	$ 1.26	$ 1.16	$ 3.69	$ 3.45	$ 1.26
Fractional i-units to be issued						0.016263
Units to be issued (in shares)	1,578,616	1,701,916				1,842,210
Average ten day trading price (usd per share)						$ 77.478