I'd suggest using a non detegent cleaner. My old refrain, the Nikwax range have various cleaners for down and Gortex type fabrics. If you do decide to use a detergent, hand wash and, add a dash of vegtable oil. That is an old trick used to wash the original 'JERSEY' oiled wool seaman's sweaters. It stops the fabric drying out to much. Start with lukewarm water. To hot and you can set the stains.