Other Matters - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2016
Other Commitments [Line Items]
Severance costs associated with workforce reduction plan		$ 9,900
Accrued severance costs		900
Loss on amendment of contract		95,908
Accrued contract amendment costs		19,582
Contract Termination
Other Commitments [Line Items]
Loss on amendment of contract	$ 95,900
Payment of loss on contract termination		$ 76,300
Contract termination date		Mar. 31, 2017
Accrued contract amendment costs		$ 19,600