Equity Activity (Reclassification and Taxes Related Tables Calculations) (Details 3) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Other comprehensive income:
Total net changes related to available-for-sale securities, before tax	$ 32	$ (24)	$ (8)
Total unrealized gains/(losses) on cash flow hedges, before tax	(454)	861	(123)
Total retirement-related benefit plans, before tax	279	(7,357)	8,767
Total net changes related to available-for-sale securities, tax	(12)	9	3
Total unrealized gains/(losses) on cash flow hedges, tax	162	(304)	47
Total retirement-related benefit plans, tax	(17)	2,615	(3,128)
Total net changes related to available-for-sale securities, net of tax	20	(15)	(5)
Total unrealized gains/(losses) on cash flow hedges, net of tax	(292)	557	(76)
Total retirement-related benefit plans, net of tax	$ 262	$ (4,742)	$ 5,639

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Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount before tax, after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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