Mortgage Servicing Rights (Schedule Of Information Relates To Serviced Loan Portfolio) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Jun. 30, 2013	Dec. 31, 2012
Transfers and Servicing [Abstract]
Balance of loans serviced for others	$ 3,911,273	$ 3,162,080
MSR as a percentage of serviced loans	0.98%	0.87%

Mortgage servicing rights, percentage of serviced loans

No definition available.

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration