Annual report pursuant to Section 13 and 15(d)

Summary of Significant Principles - Derivatives (Details)

v2.4.1.9
Summary of Significant Principles - Derivatives (Details)
12 Months Ended
Dec. 31, 2014
Accounting Policies [Abstract]  
Terminated cash flow hedges, maximum length of time over which forecasted transactions are hedges 25 years
Terminated cash flow hedges, maximum length of time over which forecasted transactions are hedged for substantial number 10 years
For open or future cash flow hedges, maximum length of time over which forecasted transactions hedged 7 years