Shareholders' Equity - Changes in AOCI Attributable to Stockholders (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
OCI before reclassifications	$ (452)	$ 226	$ 41
Amounts reclassified from AOCI	8	(14)	80
Impact of ST-Ericsson deconsolidation		60
OCI Balance	(444)	272	121
Cumulative tax impact	15us-gaap_OtherComprehensiveIncomeLossTax	(24)us-gaap_OtherComprehensiveIncomeLossTax	3us-gaap_OtherComprehensiveIncomeLossTax
OCI Balance, net of tax	(429)	248	124
Balance	580	1,024	752	631
Cumulative tax impact	33	18	42	39
Balance, net of tax	613	1,042	794	670
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
OCI before reclassifications	(116)	40	28
Amounts reclassified from AOCI	2	(28)	62
OCI Balance	(114)	12	90
Cumulative tax impact	5	(3)	(11)
OCI Balance, net of tax	(109)	9	79
Balance	(76)	38	26	(64)
Cumulative tax impact		(5)	(2)	9
Balance, net of tax	(76)	33	24	(55)
Available-For-Sale Securities [Member]
OCI before reclassifications	1	2	6
OCI Balance	1	2	6
Cumulative tax impact		3
OCI Balance, net of tax	1	5	6
Balance	2	1	(1)	(7)
Cumulative tax impact			(3)	(3)
Balance, net of tax	2	1	(4)	(10)
Accumulated Defined Benefit Plan Items [Member]
OCI before reclassifications	(65)	80	(57)
Amounts reclassified from AOCI	6	14	18
Impact of ST-Ericsson deconsolidation		11
OCI Balance	(59)	105	(39)
Cumulative tax impact	10	(24)	14
OCI Balance, net of tax	(49)	81	(25)
Balance	(159)	(100)	(205)	(166)
Cumulative tax impact	33	23	47	33
Balance, net of tax	(126)	(77)	(158)	(133)
Foreign Currency Translation Adjustments ("CTA") [Member]
OCI before reclassifications	(272)	104	64
Impact of ST-Ericsson deconsolidation		49
OCI Balance	(272)	153	64
OCI Balance, net of tax	(272)	153	64
Balance	813	1,085	932	868
Balance, net of tax	$ 813	$ 1,085	$ 932	$ 868

Accumulated Other Comprehensive Income Loss Adjustment Net Of Tax

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Accumulated Other Comprehensive Income Loss Attributable to The Company's Stockholders Net Of Tax.

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Accumulated Other Comprehensive Income Loss Before Taxes

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Amounts Reclassified From Accumulated Other Comprehensive Income Loss

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Other Comprehensive Income Impact Of Deconsolidations

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount before tax and reclassification adjustments of other comprehensive income (loss).

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Amount before tax, after reclassification adjustments of other comprehensive income (loss).

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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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