Income Taxes - Summary of Deferred Tax Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Deferred tax assets	$ 292,087	$ 234,197
Deferred tax liabilities	(482,233)	(343,746)
Net deferred tax liabilities	$ (190,146)	$ (109,549)