Related Party Transactions	12 Months Ended
Dec. 31, 2019
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Weichai Transactions See Note 3. Weichai Transactions for information regarding the Weichai SPA and Collaboration Agreement. Transactions with Joint Ventures MAT-PSI Holdings, LLC In December 2012, the Company and MAT Holdings, Inc. (“MAT”) entered into an agreement to create MAT-PSI Holdings, LLC (“MAT-PSI”), which was intended to be a holding company of its 100% Chinese wholly-owned foreign entity, referred to as Green Power. The Company invested $0.9 million for its 50% share of MAT-PSI, which was formed to manufacture, assemble and supply natural gas, gas and alternative-fueled power systems to Chinese and Asian forklift customers. The venture established a production facility in Dalian and also sourced base engines from a local Chinese factory. As MAT-PSI was not profitable, the venture was closed in 2017; however, the Company is currently in dispute with Green Power related to the wind up of the joint venture and outstanding receivables. The dispute is currently in arbitration but is not expected to have a material impact on the Company’s financial statements. Doosan-PSI, LLC In 2015, the Company and Doosan Infracore Co., Ltd. (“Doosan”), a subsidiary of Doosan Group, entered into an agreement to form Doosan-PSI, LLC. The Company invested $1.0 million to acquire 50% of the venture, which was formed to operate in the field of developing, designing, testing, manufacturing, assembling, branding, marketing, selling, distributing and providing support for industrial gas engines and all components and materials required for assembly of the gas engines to the global power generation market outside of North America and South Korea. In the fourth quarter of 2019, Doosan and the Company agreed to wind down and dissolve the joint venture. This is expected to be completed in the second quarter of 2020. Joint Venture Operating Results The Company’s investments in joint ventures are accounted for under the equity method of accounting. The Company’s Consolidated Statement of Operations included income from these investments of $0.7 million in 2019 related to the Company’s portion of the joint ventures earnings for the year. In 2018, the earnings were immaterial. The joint venture operating results are presented in Other income, net in the Company’s Consolidated Statements of Operations. Transactions with Related Individuals Industrial Electronic Controls The Company purchased $0.4 million of products in 2018 from Industrial Electronic Controls, a supplier of custom throttles, sensors, and custom electronics. Gary S. Winemaster, former Chairman of the Board, Chief Executive Officer and President and non-executive Chief Strategy Officer divested his 50% of Industrial Electronic Controls during 2018.

Related Party Transactions

Weichai Transactions

See Note 3. Weichai Transactions for information regarding the Weichai SPA and Collaboration Agreement.

Transactions with Joint Ventures

MAT-PSI Holdings, LLC

In December 2012, the Company and MAT Holdings, Inc. (“MAT”) entered into an agreement to create MAT-PSI Holdings, LLC (“MAT-PSI”), which was intended to be a holding company of its 100% Chinese wholly-owned foreign entity, referred to as Green Power. The Company invested $0.9 million for its 50% share of MAT-PSI, which was formed to manufacture, assemble and supply natural gas, gas and alternative-fueled power systems to Chinese and Asian forklift customers. The venture established a production facility in Dalian and also sourced base engines from a local Chinese factory. As MAT-PSI was not profitable, the venture was closed in 2017; however, the Company is currently in dispute with Green Power related to the wind up of the joint venture and outstanding receivables. The dispute is currently in arbitration but is not expected to have a material impact on the Company’s financial statements.

Doosan-PSI, LLC

In 2015, the Company and Doosan Infracore Co., Ltd. (“Doosan”), a subsidiary of Doosan Group, entered into an agreement to form Doosan-PSI, LLC. The Company invested $1.0 million to acquire 50% of the venture, which was formed to operate in the field of developing, designing, testing, manufacturing, assembling, branding, marketing, selling, distributing and providing support for industrial gas engines and all components and materials required for assembly of the gas engines to the global power generation market outside of North America and South Korea. In the fourth quarter of 2019, Doosan and the Company agreed to wind down and dissolve the joint venture. This is expected to be completed in the second quarter of 2020.

Joint Venture Operating Results

The Company’s investments in joint ventures are accounted for under the equity method of accounting. The Company’s Consolidated Statement of Operations included income from these investments of $0.7 million in 2019 related to the Company’s portion of the joint ventures earnings for the year. In 2018, the earnings were immaterial. The joint venture operating results are presented in Other income, net in the Company’s Consolidated Statements of Operations.

Transactions with Related Individuals

Industrial Electronic Controls

The Company purchased $0.4 million of products in 2018 from Industrial Electronic Controls, a supplier of custom throttles, sensors, and custom electronics. Gary S. Winemaster, former Chairman of the Board, Chief Executive Officer and President and non-executive Chief Strategy Officer divested his 50% of Industrial Electronic Controls during 2018.