Segment Reporting (Policies)	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Backlog Policy	Our total backlog represents the estimated transaction prices on performance obligations to our customers for which work remains to be performed. Backlog is converted into revenue in future periods as work is performed, primarily based on the cost incurred or at delivery and acceptance of products, depending on the applicable accounting method.