Acquisitions Purchase Consideration (Details) - USD ($) $ in Thousands		12 Months Ended
	Apr. 01, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned		$ 0	$ 30,164	$ 0
Payments to Acquire Businesses, Gross		0	$ 20,930	$ 0
Gatherco [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned	$ 30,200	30,164
Payments to Acquire Businesses, Gross	27,500	27,494
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Long-term Debt	1,696	1,696
Business Combination, Consideration Transferred		57,658
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents	$ (6,800)	(6,806)
Gross [Member] | Gatherco [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred		59,354
Net [Member] | Gatherco [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred		$ 52,548