Financial Instruments and Fair Value Measurements - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of an asset	$ 3,840	$ 0	$ 3,840	$ 0
Disposal group, held-for-sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of an asset			3,800
Disposal group, held-for-sale | Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of an asset	3,800		3,800
Noncontrolling Interests | Disposal group, held-for-sale | Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of an asset	$ 2,700		$ 2,700