Restructuring and Exit Activities	3 Months Ended
Mar. 31, 2021
Restructuring and Exit Activities [Abstract]
Restructuring and Exit Activities	Note K: Restructuring and Exit Activities In the third quarter of 2016, in order to streamline our operating and cost structure, we initiated the closure of our wholly-owned subsidiaries, Image Sensing Systems HK Limited (ISS HK) in Hong Kong; Image Sensing Systems (Shenzhen) Limited (ISS WOFE) in China; Image Sensing Systems Europe Limited (ISS Europe) in the United Kingdom; Image Sensing Systems Europe Limited SP.Z.O.O (ISS Poland) in Poland; and Image Sensing Systems Germany, GmbH (ISS Germany) in Germany. At December 31, 2018, Image Sensing Systems Europe Limited and Image Sensing Systems Europe Limited SP.Z.O.O were fully closed. At December 31, 2019, Image Sensing Systems Germany, GmbH was fully closed. During 2020, we initiated the closure of Image Sensing Systems EMEA Limited (ISS UK) and Image Sensing Systems Holdings Limited (ISS Holdings). At March 31, 2021, Image Sensing Systems (Shenzhen) Limited was fully closed. We incurred $16,000 and $30,000 for these entities' closure costs in the three-month periods ended March 31, 2021 and March 31, 2020, respectively.

Restructuring and Exit Activities

3 Months Ended

Mar. 31, 2021

Restructuring and Exit Activities [Abstract]

Note K: Restructuring and Exit Activities

In the third quarter of 2016, in order to streamline our operating and cost structure, we initiated the closure of our wholly-owned subsidiaries, Image Sensing Systems HK Limited (ISS HK) in Hong Kong; Image Sensing Systems (Shenzhen) Limited (ISS WOFE) in China; Image Sensing Systems Europe Limited (ISS Europe) in the United Kingdom; Image Sensing Systems Europe Limited SP.Z.O.O (ISS Poland) in Poland; and Image Sensing Systems Germany, GmbH (ISS Germany) in Germany. At December 31, 2018, Image Sensing Systems Europe Limited and Image Sensing Systems Europe Limited SP.Z.O.O were fully closed. At December 31, 2019, Image Sensing Systems Germany, GmbH was fully closed. During 2020, we initiated the closure of Image Sensing Systems EMEA Limited (ISS UK) and Image Sensing Systems Holdings Limited (ISS Holdings). At March 31, 2021, Image Sensing Systems (Shenzhen) Limited was fully closed. We incurred $16,000 and $30,000 for these entities' closure costs in the three-month periods ended March 31, 2021 and March 31, 2020, respectively.