Bank segment (Details 13) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Repurchase agreements
Gross amount of recognized liabilities	$ 142	$ 145
Net amount of liabilities presented in the Balance Sheet	142	145
Gross amount not offset in the Balance Sheet
Net amount of liabilities presented in the Balance Sheet	142	145
Financial instruments	142	145
American Savings Bank (ASB)
Repurchase agreements
Net amount of liabilities presented in the Balance Sheet	50	51
Gross amount not offset in the Balance Sheet
Net amount of liabilities presented in the Balance Sheet	50	51
Financial instruments	50	51
Commercial account holders
Repurchase agreements
Net amount of liabilities presented in the Balance Sheet	92	94
Gross amount not offset in the Balance Sheet
Net amount of liabilities presented in the Balance Sheet	92	94
Financial instruments	$ 92	$ 94