Commitments and Contingencies - Other contractual commitments and Contingencies (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Remaining payments to be made under other contractual agreements
No later than 1 year	$ 33,636	$ 51,685
Later than 1 year and no later than 5 years	185	6,241
Total	33,821	$ 57,926
Contingencies
Contingent liabilities	$ 0