Related Parties	12 Months Ended
Dec. 31, 2017
Related Party Transactions [Abstract]
Related Parties	Related Parties In June 2000, the Company entered into a stock purchase agreement with Enel pursuant to which Enel purchased 300,000 newly issued shares of its common stock for $130.7 million. To the Company’s knowledge, Enel has disposed of none of its 300,000 shares. Under the terms of the stock purchase agreement, Enel has the right to nominate one member of the Company’s board of directors. A representative of Enel served on the board until March 14, 2012; no Enel representative is presently on the board. At the time the Company entered into the stock purchase agreement with Enel, it also entered into a research and development agreement with an affiliate of Enel (the “R&D Agreement”). Under the terms of the R&D Agreement, the Company cooperated with Enel to integrate its LONWORKS technology into Enel’s remote metering management project in Italy, the Contatore Elettronico. The Company completed the sale of its components and products for the deployment phase of the Contatore Elettronico project during 2005. During 2006, the Company supplied Enel and its designated manufacturers with limited spare parts for the Contatore Elettronico system. In October 2006, the Company entered into a new development and supply agreement and a software enhancement agreement with Enel. Under the development and supply agreement, Enel and its contract manufacturers purchase additional electronic components and finished goods from the Company. Under the software enhancement agreement, the Company provided software enhancements to Enel for use in its Contatore Elettronico system. The software enhancement was assigned to S&T as part of the sale of our Grid division in September 2014. The development and supply agreement expired in March 2016. During the year ended December 31, 2017, the Company generated no revenue from products and services sold to Enel and its designated manufacturers. For the year ended December 31, 2016, the Company recognized revenue from products and services sold to Enel and its designated manufacturers of approximately $1.3 million. As of December 31, 2017 and 2016, none of the Company’s total accounts receivable balance related to amounts owed by Enel and its designated manufacturers.

Related Parties

In June 2000, the Company entered into a stock purchase agreement with Enel pursuant to which Enel purchased 300,000 newly issued shares of its common stock for $130.7 million. To the Company’s knowledge, Enel has disposed of none of its 300,000 shares. Under the terms of the stock purchase agreement, Enel has the right to nominate one member of the Company’s board of directors. A representative of Enel served on the board until March 14, 2012; no Enel representative is presently on the board.

At the time the Company entered into the stock purchase agreement with Enel, it also entered into a research and development agreement with an affiliate of Enel (the “R&D Agreement”). Under the terms of the R&D Agreement, the Company cooperated with Enel to integrate its LONWORKS technology into Enel’s remote metering management project in Italy, the Contatore Elettronico. The Company completed the sale of its components and products for the deployment phase of the Contatore Elettronico project during 2005. During 2006, the Company supplied Enel and its designated manufacturers with limited spare parts for the Contatore Elettronico system. In October 2006, the Company entered into a new development and supply agreement and a software enhancement agreement with Enel. Under the development and supply agreement, Enel and its contract manufacturers purchase additional electronic components and finished goods from the Company. Under the software enhancement agreement, the Company provided software enhancements to Enel for use in its Contatore Elettronico system. The software enhancement was assigned to S&T as part of the sale of our Grid division in September 2014. The development and supply agreement expired in March 2016.

During the year ended December 31, 2017, the Company generated no revenue from products and services sold to Enel and its designated manufacturers. For the year ended December 31, 2016, the Company recognized revenue from products and services sold to Enel and its designated manufacturers of approximately $1.3 million. As of December 31, 2017 and 2016, none of the Company’s total accounts receivable balance related to amounts owed by Enel and its designated manufacturers.