v3.7.0.1
Derivative and Financial Instruments (Details Textual) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2017
Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosures [Line Items]    
Aggregate fair value of all derivative instruments in a liability position $ 35 $ 42
Collateral was posted for derivative instruments in a liability position 0 $ 0
In event of downgrade below investment grade [Member]    
Derivative Instruments and Hedging Activities Disclosures [Line Items]    
Additional collateral, either in the form of cash or letters of credit $ 35  
Financial instruments [Member]    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Terms of financial instruments and trade receivables 90 days  
Trade receivables [Member]    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Terms of financial instruments and trade receivables 30 days