Variable Interest Entities - Carrying Amounts and Classification of Consolidated VIE Assets and Liabilities (Details)
$ in Thousands
12 Months Ended
Dec. 31, 2015
USD ($)
entity
Dec. 31, 2014
USD ($)
entity
Consolidated variable interest entities    
Variable Interest Entity [Line Items]    
Primary beneficiary, number of entities | entity 14 5
Variable interest entity, assets and liabilities included    
Variable Interest Entity [Line Items]    
VIE, total assets $ 791,364 $ 241,659
VIE, total liabilities 450,553 240,265
Current assets | Variable interest entity, assets and liabilities included    
Variable Interest Entity [Line Items]    
VIE, total assets 212,295 30,878
Non-current assets | Variable interest entity, assets and liabilities included    
Variable Interest Entity [Line Items]    
VIE, total assets 579,069 210,781
Current liabilities | Variable interest entity, assets and liabilities included    
Variable Interest Entity [Line Items]    
VIE, total liabilities 370,395 5,000
Non-current liabilities | Variable interest entity, assets and liabilities included    
Variable Interest Entity [Line Items]    
VIE, total liabilities $ 80,158 $ 235,265