Segment Information (Entity-Wide Disclosures) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Segment Reporting Information [Line Items]
Customer revenues	$ 376,088	$ 389,277
Customer Revenues [Member]
Segment Reporting Information [Line Items]
Customer revenues	376,088	389,277
CAM [Member]
Segment Reporting Information [Line Items]
Customer revenues	83,277	74,163
CAM [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
Customer revenues	60,800	46,736
All other [Member]
Segment Reporting Information [Line Items]
Customer revenues	93,698	80,036
All other [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
Customer revenues	$ 68,162	$ 58,380