Commitments, Contingencies and Litigation - (Additional Information) (Details) - USD ($) $ in Thousands	1 Months Ended			9 Months Ended	12 Months Ended
	Jul. 31, 2017	Jun. 30, 2017	Feb. 29, 2016	Dec. 31, 2017	Mar. 31, 2017
Commitments, Contingencies And Litigation [Line Items]
Reserves for anti-competition investigations				$ 2,058	$ 25,551
Provision for environmental liabilities				1,117	1,123
Belgium Anti-Competition Proceeding
Commitments, Contingencies And Litigation [Line Items]
Penalties paid relating to anti-competition investigations			$ 1,962
Reserves for anti-competition investigations				2,058	1,830
Germany Anti-Competition Proceeding
Commitments, Contingencies And Litigation [Line Items]
Penalties paid relating to anti-competition investigations		$ 14,811
Reserves for anti-competition investigations				0	13,463
Estimate of possible loss				11,415
Dutch Anti-Competition Proceeding
Commitments, Contingencies And Litigation [Line Items]
Penalties paid relating to anti-competition investigations	$ 11,229
Reserves for anti-competition investigations				$ 0	$ 10,258