Segment Information (Entity-Wide Disclosures) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Segment Reporting Information [Line Items]
Customer revenues	$ 177,385	$ 147,025
Customer Revenues [Member]
Segment Reporting Information [Line Items]
Customer revenues	177,385	147,025
CAM [Member]
Segment Reporting Information [Line Items]
Customer revenues	51,726	42,854
CAM [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
Customer revenues	28,761	19,881
All other [Member]
Segment Reporting Information [Line Items]
Customer revenues	55,011	35,606
All other [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
Customer revenues	$ 33,668	$ 21,676