Annual and transition report of foreign private issuers pursuant to Section 13 or 15(d)

Fair value measurements (Carrying amounts and fair values of financial instruments) (Details)

v3.8.0.1
Fair value measurements (Carrying amounts and fair values of financial instruments) (Details) - USD ($)
$ in Thousands
Dec. 31, 2017
Dec. 31, 2016
Carrying value    
Assets    
Cash and cash equivalents $ 1,659,669 $ 2,035,447
Restricted cash 364,456 329,180
Derivative assets 48,896 37,187
Notes receivables 22,497 23,359
Assets, Fair value 2,095,518 2,425,173
Liabilities    
Debt [1] 28,580,800 27,873,900
Guarantees 2,272 51,804
Liabilities, Fair value 28,583,072 27,925,704
Fair value    
Assets    
Cash and cash equivalents 1,659,669 2,035,447
Restricted cash 364,456 329,180
Derivative assets 48,896 37,187
Notes receivables 22,497 23,359
Assets, Fair value 2,095,518 2,425,173
Liabilities    
Debt 29,074,375 28,203,635
Guarantees 2,272 51,804
Liabilities, Fair value 29,076,647 28,255,439
Fair value | Level 1    
Assets    
Cash and cash equivalents 1,659,669 2,035,447
Restricted cash 364,456 329,180
Derivative assets 0 0
Notes receivables 0 0
Assets, Fair value 2,024,125 2,364,627
Liabilities    
Debt 0 0
Guarantees 0 0
Liabilities, Fair value 0 0
Fair value | Level 2    
Assets    
Cash and cash equivalents 0 0
Restricted cash 0 0
Derivative assets 48,896 37,187
Notes receivables 22,497 23,359
Assets, Fair value 71,393 60,546
Liabilities    
Debt 29,074,375 28,203,635
Guarantees 0 0
Liabilities, Fair value 29,074,375 28,203,635
Fair value | Level 3    
Assets    
Cash and cash equivalents 0 0
Restricted cash 0 0
Derivative assets 0 0
Notes receivables 0 0
Assets, Fair value 0 0
Liabilities    
Debt 0 0
Guarantees 2,272 51,804
Liabilities, Fair value $ 2,272 $ 51,804
[1] Excludes debt issuance costs and debt discounts.