XML 61 R156.htm IDEA: XBRL DOCUMENT v2.4.1.9
Netting Arrangements for Certain Financial Instruments - Additional Information (Detail) (USD $)
In Billions, unless otherwise specified
Dec. 31, 2014
Derivative [Line Items]  
Notional amount of derivative $ 140.6invest_DerivativeNotionalAmount
Exchange Cleared [Member]  
Derivative [Line Items]  
Notional amount of derivative 33.0invest_DerivativeNotionalAmount
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeClearedMember
Exchange Traded [Member]  
Derivative [Line Items]  
Notional amount of derivative $ 4.2invest_DerivativeNotionalAmount
/ us-gaap_TransactionTypeAxis
= us-gaap_ExchangeTradedMember