Segment Reporting (Reportable Segments Consolidated Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Total Assets	$ 9,111,394	$ 8,420,562
Operating Segments [Member]
Total Assets	8,905,446	8,033,884
Operating Segments [Member] | Industrial Operations
Total Assets	8,709,960	7,843,302
Operating Segments [Member] | Non-reportable segments
Total Assets	35,292	39,700
Operating Segments [Member] | Service Operations [Member]
Total Assets	160,194	150,882
Corporate, Non-Segment [Member]
Total Assets	$ 205,948	$ 386,678