Other Comprehensive Income (Loss) (Schedule Of Accumulated Other Comprehensive Income, Net Of Tax) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Beginning Balance			$ 247,734	$ 154,250
Other comprehensive income (loss)	21,448	41,464	26,989	89,803
Ending Balance	274,723	244,053	274,723	244,053
Securities Available For Sale [Member]
Beginning Balance			227,052	96,012
Other comprehensive income (loss)			41,010	106,016
Ending Balance	268,062	202,028	268,062	202,028
Defined Benefit Plans [Member]
Beginning Balance			(42,958)	(28,357)
Other comprehensive income (loss)			2,655	1,526
Ending Balance	(40,303)	(26,831)	(40,303)	(26,831)
Derivatives [Member]
Beginning Balance			63,640	86,595
Other comprehensive income (loss)			(16,676)	(17,739)
Ending Balance	$ 46,964	$ 68,856	$ 46,964	$ 68,856