XML 27 R31.htm IDEA: XBRL DOCUMENT v3.3.0.814
Fair Value Measurements (Details) - USD ($)
$ in Thousands
9 Months Ended 12 Months Ended
Sep. 30, 2015
Dec. 31, 2014
Sep. 30, 2014
Dec. 31, 2013
Financial Instruments        
Cash and cash equivalents $ 865,425 $ 471,901 $ 573,067 $ 830,014
Institutional | Minimum        
Financial Instruments        
Fair value assumption, interest rate 0.00% 0.00%    
Institutional | Maximum        
Financial Instruments        
Fair value assumption, interest rate 7.73% 7.25%    
Fair Value | Level 1        
Financial Instruments        
Cash and cash equivalents $ 865,425 $ 471,901    
Fair Value | Level 2 | Retail        
Financial Instruments        
Long-term debt 1,460,294 1,414,105    
Fair Value | Level 2 | Institutional        
Financial Instruments        
Long-term debt 489,373 513,647    
Fair Value | Level 2 | Other        
Financial Instruments        
Long-term debt 221,538 4,675    
Book Value        
Financial Instruments        
Cash and cash equivalents 865,425 471,901    
Book Value | Retail        
Financial Instruments        
Long-term debt 1,453,250 1,453,250    
Book Value | Institutional        
Financial Instruments        
Long-term debt 532,940 532,722    
Book Value | Other        
Financial Instruments        
Long-term debt $ 220,922 $ 4,749