0000935494 2020-10-30 2020-10-30 false NATIONAL INSTRUMENTS CORP 0000935494 8-K 2020-10-30 000-25426 DE 74-1871327 11500 North Mopac Expressway Austin TX 78759 512 683-0100 false false false false Common Stock, $0.01 par value NATI NASDAQ false