Other Non-Current Liabilities - Other Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Other Liabilities Disclosure [Abstract]
Pension and post-employment benefits	$ 73,341	$ 73,683
Deferred compensation	44,564	41,992
Uncertain tax positions	123,793	101,908
Other	25,177	32,808
Other non-current liabilities	$ 266,875	$ 250,391