Loans and Allowance for Loan Losses (Schedule Of Allowances For Loan Losses And Recorded Investment In Loans) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance, allowance	$ 254,702	$ 277,783	$ 261,317	$ 307,560
Allowance for loan losses of sold loans				(1,019)
Charge-offs	(14,843)	(22,761)	(46,072)	(87,117)
Recoveries	8,085	10,511	21,665	24,314
Provision for loan losses	2,956	3,843	13,990	25,638
Ending balance, allowance	250,900	269,376	250,900	269,376
Ending balance: individually evaluated for impairment, allowance	31,441	39,165	31,441	39,165
Ending balance: collectively evaluated for impairment, allowance	219,459	230,211	219,459	230,211
Total loans	21,892,675	20,617,415	21,892,675	20,617,415	$ 21,128,489
Ending balance: individually evaluated for impairment, loans	309,344	537,540	309,344	537,540
Ending balance: collectively evaluated for impairment, loans	21,583,331	20,079,875	21,583,331	20,079,875
Deferred fees and costs, net	28,400	28,800	28,400	28,800	$ 30,800
Commercial Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance, allowance	90,691	104,394	101,471	127,646
Allowance for loan losses of sold loans				(281)
Charge-offs	(1,722)	(5,233)	(12,120)	(41,139)
Recoveries	4,019	3,099	10,500	8,318
Provision for loan losses	(3,982)	(271)	(10,845)	7,445
Ending balance, allowance	89,006	101,989	89,006	101,989
Ending balance: individually evaluated for impairment, allowance	18,091	22,107	18,091	22,107
Ending balance: collectively evaluated for impairment, allowance	70,915	79,882	70,915	79,882
Total loans	7,190,257	6,774,794	7,190,257	6,774,794
Ending balance: individually evaluated for impairment, loans	159,582	317,011	159,582	317,011
Ending balance: collectively evaluated for impairment, loans	7,030,675	6,457,783	7,030,675	6,457,783
Commercial and Industrial [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance, allowance	123,050	130,814	118,110	115,435
Allowance for loan losses of sold loans				(398)
Charge-offs	(8,342)	(11,306)	(17,417)	(26,896)
Recoveries	2,203	5,257	5,774	9,562
Provision for loan losses	5,510	78	15,954	27,140
Ending balance, allowance	122,421	124,843	122,421	124,843
Ending balance: individually evaluated for impairment, allowance	12,568	15,863	12,568	15,863
Ending balance: collectively evaluated for impairment, allowance	109,853	108,980	109,853	108,980
Total loans	10,543,176	9,987,660	10,543,176	9,987,660
Ending balance: individually evaluated for impairment, loans	109,904	172,860	109,904	172,860
Ending balance: collectively evaluated for impairment, loans	10,433,272	9,814,800	10,433,272	9,814,800
Retail [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance, allowance	40,961	42,575	41,736	41,479
Allowance for loan losses of sold loans				(340)
Charge-offs	(4,779)	(6,222)	(16,535)	(19,082)
Recoveries	1,863	2,155	5,391	6,434
Provision for loan losses	1,428	4,036	8,881	14,053
Ending balance, allowance	39,473	42,544	39,473	42,544
Ending balance: individually evaluated for impairment, allowance	783	1,195	783	1,195
Ending balance: collectively evaluated for impairment, allowance	38,690	41,349	38,690	41,349
Total loans	4,159,243	3,854,961	4,159,243	3,854,961
Ending balance: individually evaluated for impairment, loans	39,858	47,669	39,858	47,669
Ending balance: collectively evaluated for impairment, loans	4,119,385	3,807,292	4,119,385	3,807,292
Unallocated [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance, allowance	0	0	0	23,000
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision for loan losses	0	0	0	(23,000)
Ending balance, allowance	0	0	0	0
Ending balance: individually evaluated for impairment, allowance	0	0	0	0
Ending balance: collectively evaluated for impairment, allowance	0	0	0	0
Total loans	0	0	0	0
Ending balance: individually evaluated for impairment, loans	0	0	0	0
Ending balance: collectively evaluated for impairment, loans	$ 0	$ 0	$ 0	$ 0