Investments - Aggregated Balance Sheet Information (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Aggregated balance sheet information [Abstract]
Current assets	$ 847,444	$ 586,287
Non-current assets	677,069	105,630
Total Assets	1,524,513	691,917
Current liabilities	475,582	224,459
Non-current liabilities	150,411	136,321
Equity	898,519	331,137
Total Liabilities and Equity	$ 1,524,513	$ 691,917