Significant Accounting Policies Credit Policy - Chapter 7 Bankruptcy Loans (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Jun. 30, 2013
PerformingsecondlienloansreturnedtoaccrualstatusaftersixmonthsChapter7bankruptcy [Line Items]
PerformingSecondLienLoansaftersixmonthsofperformancepostChapter7bankruptcy	$ 220

PerformingSecondLienLoansaftersixmonthsofperformancepostChapter7bankruptcy

No definition available.

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