Note 7 - Redeemable Noncontrolling Interests (Details Textual) - USD ($) $ in Millions	Jul. 29, 2019	Jun. 22, 2018
TM4 Inc. [Member]
Temporary Equity, Stock Issued During Period, Value, New Issues		$ 102
TM4 Inc. [Member] | Hydro-Québec [Member]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners		45.00%
S.M.E. S.p.A. [Member] | Hydro-Québec [Member]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	45.00%
Prestolite E-Propulsion Systems (Beijing) Limited [Member] | Hydro-Québec [Member]
Minority Interest, Ownership Percentage by Noncontrolling Owners, Increase	22.50%
SME and PEPS [Member]
Temporary Equity, Increase from Sale of Parent Equity Interest	$ 64