Commitments and Contingencies (Details)	9 Months Ended
	Sep. 30, 2017
Loss Contingencies [Line Items]
Percentage of royalty obligations, majority are less than	3.00%
Minimum
Loss Contingencies [Line Items]
Percentage of royalty obligations	0.50%
Maximum
Loss Contingencies [Line Items]
Percentage of royalty obligations	5.00%