Condensed Consolidating Financial Statements - Condensed Consolidating Balance Sheet (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Current assets:
Cash and equivalents	$ 4,388	$ 5,301	$ 3,296	$ 2,649
Accounts receivable	4,050us-gaap_AccountsReceivableNetCurrent	4,370us-gaap_AccountsReceivableNetCurrent
Contracts in process	4,591gd_ContractsInProcess	4,780gd_ContractsInProcess
Inventories
Pre-owned aircraft	75gd_InventoryPreOwnedAircraft	18gd_InventoryPreOwnedAircraft
Other current assets	1,157us-gaap_OtherAssetsCurrent	821us-gaap_OtherAssetsCurrent
Total current assets	17,407us-gaap_AssetsCurrent	18,162us-gaap_AssetsCurrent
Noncurrent assets:
Property, plant and equipment	7,292us-gaap_PropertyPlantAndEquipmentGross	7,152us-gaap_PropertyPlantAndEquipmentGross
Accumulated depreciation of PP&E	(3,963)	(3,793)
Accumulated amortization of intangible assets	(1,486)	(1,538)
Goodwill	11,731us-gaap_Goodwill	11,932us-gaap_Goodwill	12,003us-gaap_Goodwill
Other assets	1,976us-gaap_OtherAssetsNoncurrent	997us-gaap_OtherAssetsNoncurrent
Total noncurrent assets	17,948us-gaap_AssetsNoncurrent	17,332us-gaap_AssetsNoncurrent
Total assets	35,355us-gaap_Assets	35,494us-gaap_Assets	34,309us-gaap_Assets
Current liabilities:
Customer advances and deposits	7,335	6,584
Total current liabilities	13,751us-gaap_LiabilitiesCurrent	12,259us-gaap_LiabilitiesCurrent
Noncurrent liabilities:
Long-term debt	3,410us-gaap_LongTermDebtNoncurrent	3,908us-gaap_LongTermDebtNoncurrent
Other liabilities	6,365us-gaap_OtherLiabilitiesNoncurrent	4,826us-gaap_OtherLiabilitiesNoncurrent
Total noncurrent liabilities	9,775us-gaap_LiabilitiesNoncurrent	8,734us-gaap_LiabilitiesNoncurrent
Shareholders’ equity:
Common stock	482us-gaap_CommonStockValue	482us-gaap_CommonStockValue
Total shareholders’ equity	11,829us-gaap_StockholdersEquity	14,501us-gaap_StockholdersEquity	11,390us-gaap_StockholdersEquity	13,232us-gaap_StockholdersEquity
Total liabilities and shareholders’ equity	35,355	35,494
Parent
Current assets:
Cash and equivalents	2,536	4,179	2,300	1,572
Accounts receivable	0	0
Contracts in process	542	571
Inventories
Work in process	0	0
Raw materials	0	0
Finished goods	0	0
Pre-owned aircraft	0	0
Other current assets	781	424
Total current assets	3,859	5,174
Noncurrent assets:
Property, plant and equipment	148	156
Accumulated depreciation of PP&E	(52)	(64)
Intangible assets	0	0
Accumulated amortization of intangible assets	0	0
Goodwill	0	0
Other assets	1,479	460
Investment in subsidiaries	37,449	35,211
Total noncurrent assets	39,024	35,763
Total assets	42,883	40,937
Short-term Debt	500
Current liabilities:
Customer advances and deposits	0	0
Other current liabilities	1,298	868
Total current liabilities	1,798	868
Noncurrent liabilities:
Long-term debt	3,386	3,883
Other liabilities	3,514	2,333
Total noncurrent liabilities	6,900	6,216
Intercompany	22,356	19,352
Shareholders’ equity:
Common stock	482	482
Other shareholders' equity	11,347	14,019
Total shareholders’ equity	11,829	14,501
Total liabilities and shareholders’ equity	42,883	40,937
Guarantors on a Combined Basis
Current assets:
Cash and equivalents	0	0	0	0
Accounts receivable	1,379	1,451
Contracts in process	2,966	3,124
Inventories
Work in process	1,818	1,623
Raw materials	1,260	1,172
Finished goods	20	24
Pre-owned aircraft	75	18
Other current assets	215	203
Total current assets	7,733	7,615
Noncurrent assets:
Property, plant and equipment	6,035	5,827
Accumulated depreciation of PP&E	(3,246)	(3,062)
Intangible assets	1,484	1,614
Accumulated amortization of intangible assets	(1,042)	(1,111)
Goodwill	8,095	8,041
Other assets	213	211
Investment in subsidiaries	0	0
Total noncurrent assets	11,539	11,520
Total assets	19,272	19,135
Short-term Debt	1
Current liabilities:
Customer advances and deposits	3,529	3,493
Other current liabilities	3,511	3,644
Total current liabilities	7,041	7,137
Noncurrent liabilities:
Long-term debt	24	25
Other liabilities	2,369	2,007
Total noncurrent liabilities	2,393	2,032
Intercompany	(22,557)	(19,956)
Shareholders’ equity:
Common stock	6	6
Other shareholders' equity	32,389	29,916
Total shareholders’ equity	32,395	29,922
Total liabilities and shareholders’ equity	19,272	19,135
Other Subsidiaries on a Combined Basis
Current assets:
Cash and equivalents	1,852	1,122	996	1,077
Accounts receivable	2,671	2,919
Contracts in process	1,083	1,085
Inventories
Work in process	10	10
Raw materials	30	38
Finished goods	8	5
Pre-owned aircraft	0	0
Other current assets	161	194
Total current assets	5,815	5,373
Noncurrent assets:
Property, plant and equipment	1,109	1,169
Accumulated depreciation of PP&E	(665)	(667)
Intangible assets	914	968
Accumulated amortization of intangible assets	(444)	(427)
Goodwill	3,636	3,891
Other assets	284	326
Investment in subsidiaries	0	0
Total noncurrent assets	4,834	5,260
Total assets	10,649	10,633
Short-term Debt	0
Current liabilities:
Customer advances and deposits	3,806	3,091
Other current liabilities	1,106	1,163
Total current liabilities	4,912	4,254
Noncurrent liabilities:
Long-term debt	0	0
Other liabilities	482	486
Total noncurrent liabilities	482	486
Intercompany	201	604
Shareholders’ equity:
Common stock	2,043	3,570
Other shareholders' equity	3,011	1,719
Total shareholders’ equity	5,054	5,289
Total liabilities and shareholders’ equity	10,649	10,633
Consolidating Adjustments
Current assets:
Cash and equivalents	0	0	0	0
Accounts receivable	0	0
Contracts in process	0	0
Inventories
Work in process	0	0
Raw materials	0	0
Finished goods	0	0
Pre-owned aircraft	0	0
Other current assets	0	0
Total current assets	0	0
Noncurrent assets:
Property, plant and equipment	0	0
Accumulated depreciation of PP&E	0	0
Intangible assets	0	0
Accumulated amortization of intangible assets	0	0
Goodwill	0	0
Other assets	0	0
Investment in subsidiaries	(37,449)	(35,211)
Total noncurrent assets	(37,449)	(35,211)
Total assets	(37,449)	(35,211)
Short-term Debt	0
Current liabilities:
Customer advances and deposits	0	0
Other current liabilities	0	0
Total current liabilities	0	0
Noncurrent liabilities:
Long-term debt	0	0
Other liabilities	0	0
Total noncurrent liabilities	0	0
Intercompany	0	0
Shareholders’ equity:
Common stock	(2,049)	(3,576)
Other shareholders' equity	(35,400)	(31,635)
Total shareholders’ equity	(37,449)	(35,211)
Total liabilities and shareholders’ equity	(37,449)	(35,211)
Total Consolidated
Current assets:
Cash and equivalents	4,388	5,301	3,296	2,649
Accounts receivable	4,050	4,370
Contracts in process	4,591	4,780
Inventories
Work in process	1,828	1,633
Raw materials	1,290	1,210
Finished goods	28	29
Pre-owned aircraft	75	18
Other current assets	1,157	821
Total current assets	17,407	18,162
Noncurrent assets:
Property, plant and equipment	7,292	7,152
Accumulated depreciation of PP&E	(3,963)	(3,793)
Intangible assets	2,398	2,582
Accumulated amortization of intangible assets	(1,486)	(1,538)
Goodwill	11,731	11,932
Other assets	1,976	997
Investment in subsidiaries	0	0
Total noncurrent assets	17,948	17,332
Total assets	35,355	35,494
Short-term Debt	501
Current liabilities:
Customer advances and deposits	7,335	6,584
Other current liabilities	5,915	5,675
Total current liabilities	13,751	12,259
Noncurrent liabilities:
Long-term debt	3,410	3,908
Other liabilities	6,365	4,826
Total noncurrent liabilities	9,775	8,734
Intercompany	0	0
Shareholders’ equity:
Common stock	482	482
Other shareholders' equity	11,347	14,019
Total shareholders’ equity	11,829	14,501
Total liabilities and shareholders’ equity	$ 35,355	$ 35,494

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