CONTRACT & OTHER DEFERRED ASSETS AND PROGRESS COLLECTIONS & DEFERRED INCOME - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Contractors [Abstract]
Revenue recognized included in contract liability	$ 5,747	$ 6,254
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Increase in contract assets	424
Increase in revenue in excess of billings for equipment contracts due to timing of revenue recognized for work performed	398
Increase in non-recurring engineering costs	102
Increase in deferred inventory costs	390
Aviation
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Increase in revenue in excess of billings for equipment contracts due to timing of revenue recognized for work performed	138
Increase in non-recurring engineering costs	69
Power
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Increase in deferred inventory costs	214
Transportation
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Increase in revenue in excess of billings for equipment contracts due to timing of revenue recognized for work performed	56
Oil & Gas
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Increase in deferred inventory costs	201
Healthcare
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Increase in revenue in excess of billings for equipment contracts due to timing of revenue recognized for work performed	158
Restatement Adjustment | Adjustment Due to Change in Estimated Profitability
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Change in gross profit	178
Restatement Adjustment | Adjustment Due to Change in Estimated Profitability | Aviation
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Change in gross profit	81
Restatement Adjustment | Adjustment Due to Change in Estimated Profitability | Power
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Change in gross profit	$ 74