XML 53 R31.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Research and Development Costs (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2017
Research and Development [Abstract] |
Schedule of Research and Development Costs |
| Year Ended December 31,
(millions of dollars) | 2017 |  | 2016 |  | 2015
Gross R&D expenditures | $ | 473.1 |  |  | $ | 417.8 |  |  | $ | 386.2 |
Customer reimbursements | (65.6 | ) |  | (74.6 | ) |  | (78.8 | )
Net R&D expenditures | $ | 407.5 |  |  | $ | 343.2 |  |  | $ | 307.4 |

X
- Definition Schedule of Research and Development Costs [Table Text Block]. + References No definition available. + Details
Name: | bwa_ScheduleOfResearchAndDevelopmentCostsTableTextBlock
Namespace Prefix: | bwa_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_ResearchAndDevelopmentAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration