Reconciliations of depreciation and amortization (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Reconciliation of Depreciation and amortization
Depreciation and amortization	$ 587	$ 608	$ 1,173	$ 1,222
Operating Segments | Reportable Segments
Reconciliation of Depreciation and amortization
Depreciation and amortization	493	512	989	1,027
Operating Segments | Reportable Segments | Construction Industries
Reconciliation of Depreciation and amortization
Depreciation and amortization	59	61	118	122
Operating Segments | Reportable Segments | Resource Industries
Reconciliation of Depreciation and amortization
Depreciation and amortization	101	104	200	207
Operating Segments | Reportable Segments | Energy & Transportation
Reconciliation of Depreciation and amortization
Depreciation and amortization	142	149	284	295
Operating Segments | Reportable Segments | Financial Products Segment
Reconciliation of Depreciation and amortization
Depreciation and amortization	191	198	387	403
Intersegment Eliminations | All Other operating segments
Reconciliation of Depreciation and amortization
Depreciation and amortization	60	63	122	125
Intersegment Eliminations | Cost Centers
Reconciliation of Depreciation and amortization
Depreciation and amortization	24	32	50	65
Intersegment Eliminations | Other
Reconciliation of Depreciation and amortization
Depreciation and amortization	$ 10	$ 1	$ 12	$ 5