Note 2 - Acquisitions	6 Months Ended
Jun. 30, 2021
Notes to Financial Statements
Business Combination Disclosure [Text Block]	Note 2. Acquisitions Pi Innovo Holding Limited — On March 1, 2021, we acquired the remaining 51% ownership interest in Pi Innovo Holding Limited (Pi Innovo). Pi Innovo designs, develops and manufactures electronic control units spanning a range of applications and industries. The acquisition of the remaining ownership interest provides us with a 100% ownership interest in Pi Innovo. The total purchase consideration of $35 is comprised of $18 of cash paid at closing and the $17 fair value of our previously held equity method investment in Pi Innovo. The results of operations of the business are reported within our Commercial Vehicle operating segment. The pro forma effects of this acquisition would not materially impact our reported results for any period presented, and as a result no pro forma financial information is presented. Ashwoods Innovations Limited — On February 5, 2020, we acquired Curtis Instruments, Inc.'s (Curtis) 35.4% ownership interest in Ashwoods Innovations Limited (Ashwoods). Ashwoods designs and manufactures permanent magnet electric motors for the automotive, material handling and off-highway vehicle markets. The acquisition of Curtis' interest in Ashwoods, along with our existing ownership interest in Ashwoods, provided us with a 97.8% ownership interest and a controlling financial interest in Ashwoods. We recognized a $3 gain to other income (expense), net on the required remeasurement of our previously held equity method investment in Ashwoods to fair value. The total purchase consideration of $22 is comprised of $8 of cash paid to Curtis at closing, the $10 fair value of our previously held equity method investment in Ashwoods and $4 related to the effective settlement of a pre-existing loan payable due from Ashwoods. During March 2020, we acquired the remaining noncontrolling interests in Ashwoods held by employee shareholders. See Hydro-Québec relationship discussion below for details of subsequent changes in our ownership interest in Ashwoods. The results of operations of the business are reported within our Off-Highway operating segment. The pro forma effects of this acquisition would not materially impact our reported results for any period presented, and as a result no pro forma financial information is presented. Hydro-Québec Relationship — On April 14, 2020, Hydro-Québec acquired an indirect 45% redeemable noncontrolling interest in Ashwoods. We received $9 in cash at closing, inclusive of $2 in proceeds on a loan from Hydro-Québec. Dana will continue to consolidate Ashwoods as the governing documents continue to provide Dana with a controlling financial interest in this subsidiary.

Note 2 - Acquisitions

6 Months Ended

Jun. 30, 2021

Business Combination Disclosure [Text Block]

Pi Innovo Holding Limited — On March 1, 2021, we acquired the remaining 51% ownership interest in Pi Innovo Holding Limited (Pi Innovo). Pi Innovo designs, develops and manufactures electronic control units spanning a range of applications and industries. The acquisition of the remaining ownership interest provides us with a 100% ownership interest in Pi Innovo. The total purchase consideration of $35 is comprised of $18 of cash paid at closing and the $17 fair value of our previously held equity method investment in Pi Innovo. The results of operations of the business are reported within our Commercial Vehicle operating segment. The pro forma effects of this acquisition would not materially impact our reported results for any period presented, and as a result no pro forma financial information is presented.

Ashwoods Innovations Limited — On February 5, 2020, we acquired Curtis Instruments, Inc.'s (Curtis) 35.4% ownership interest in Ashwoods Innovations Limited (Ashwoods). Ashwoods designs and manufactures permanent magnet electric motors for the automotive, material handling and off-highway vehicle markets. The acquisition of Curtis' interest in Ashwoods, along with our existing ownership interest in Ashwoods, provided us with a 97.8% ownership interest and a controlling financial interest in Ashwoods. We recognized a $3 gain to other income (expense), net on the required remeasurement of our previously held equity method investment in Ashwoods to fair value. The total purchase consideration of $22 is comprised of $8 of cash paid to Curtis at closing, the $10 fair value of our previously held equity method investment in Ashwoods and $4 related to the effective settlement of a pre-existing loan payable due from Ashwoods. During March 2020, we acquired the remaining noncontrolling interests in Ashwoods held by employee shareholders. See Hydro-Québec relationship discussion below for details of subsequent changes in our ownership interest in Ashwoods. The results of operations of the business are reported within our Off-Highway operating segment. The pro forma effects of this acquisition would not materially impact our reported results for any period presented, and as a result no pro forma financial information is presented.

Hydro-Québec Relationship — On April 14, 2020, Hydro-Québec acquired an indirect 45% redeemable noncontrolling interest in Ashwoods. We received $9 in cash at closing, inclusive of $2 in proceeds on a loan from Hydro-Québec. Dana will continue to consolidate Ashwoods as the governing documents continue to provide Dana with a controlling financial interest in this subsidiary.