CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Millions, unless otherwise specified	3 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Net income	$ 1,569us-gaap_ProfitLoss	$ 1,407us-gaap_ProfitLoss
Investment securities, available-for-sale:
Net unrealized (loss) gain	(10)	17
Income tax effect	3	(6)
Reclassification adjustment for net gain realized in net income	(21)	0
Income tax effect	8	0
Defined benefit pension and other postretirement plans:
Net unrealized actuarial gain and prior service credit	6	1
Income tax effect	(1)	0
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Gain (Loss), before Tax	(1)	(2)
Income tax effect	0	1
Derivative instruments classified as cash flow hedges:
Net unrealized gain	63	24
Income tax effect	(17)	(4)
Reclassification adjustment for net gain realized in net income	(6)	(11)
Income tax effect	2	2
Foreign currency translation adjustments	1	0
Other comprehensive income, net of tax	27	22
Comprehensive income	$ 1,596	$ 1,429

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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