Segment Information (Entity-Wide Disclosures) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Segment Reporting Information [Line Items]
Customer revenues	$ 237,917	$ 177,385
Customer Revenues [Member]
Segment Reporting Information [Line Items]
Customer revenues	237,917	177,385
CAM [Member]
Segment Reporting Information [Line Items]
Customer revenues	47,978	51,726
CAM [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
Customer revenues	30,782	28,761
All other [Member]
Segment Reporting Information [Line Items]
Customer revenues	89,206	55,011
All other [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
Customer revenues	$ 62,186	$ 33,668