Loans And Allowance For Credit Losses (Summary Of ALLL And Outstanding Loan Balances According To The Company's Impairment Method) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Individually evaluated for impairment	$ (64,566)	$ (49,525)
Allowance for loan losses: Collectively evaluated for impairment	502,388	555,578
Allowance for loan losses: Purchased loans with evidence of credit deterioration	568	945
Allowance for loan losses: Total	567,522	606,048	$ 604,663
Loans and Leases Receivable, Gross	42,649,265	40,649,542
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Individually evaluated for impairment	(55,951)	(36,909)
Allowance for loan losses: Collectively evaluated for impairment	364,703	417,295
Allowance for loan losses: Purchased loans with evidence of credit deterioration	66	73
Allowance for loan losses: Total	420,720	454,277	412,514
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Individually evaluated for impairment	(2,620)	(3,154)
Allowance for loan losses: Collectively evaluated for impairment	113,202	110,417
Allowance for loan losses: Purchased loans with evidence of credit deterioration	105	421
Allowance for loan losses: Total	115,927	113,992	145,009
Loans and Leases Receivable, Gross	2,018,655	1,841,502
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Individually evaluated for impairment	(5,995)	(9,462)
Allowance for loan losses: Collectively evaluated for impairment	24,483	27,866
Allowance for loan losses: Purchased loans with evidence of credit deterioration	397	451
Allowance for loan losses: Total	30,875	37,779	$ 47,140
Loans and Leases Receivable, Gross	189,794	187,149
Outstanding Loan Balances [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Outstanding loan balances: Individually evaluated for impairment	619,440	489,575
Outstanding loan balances: Collectively evaluated for impairment	41,952,653	40,035,044
Loans and Leases Receivable, Gross	42,649,265	40,649,542
Financing Receivable, Acquired Deteriorated Credit Quality	77,172	124,923
Outstanding Loan Balances [Member] \| Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Outstanding loan balances: Individually evaluated for impairment	466,187	289,629
Outstanding loan balances: Collectively evaluated for impairment	21,111,071	21,129,125
Loans and Leases Receivable, Gross	21,614,997	21,479,014
Financing Receivable, Acquired Deteriorated Credit Quality	37,739	60,260
Outstanding Loan Balances [Member] \| Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Outstanding loan balances: Individually evaluated for impairment	78,190	107,341
Outstanding loan balances: Collectively evaluated for impairment	11,230,486	10,193,840
Loans and Leases Receivable, Gross	11,340,793	10,355,903
Financing Receivable, Acquired Deteriorated Credit Quality	32,117	54,722
Outstanding Loan Balances [Member] \| Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Outstanding loan balances: Individually evaluated for impairment	75,063	92,605
Outstanding loan balances: Collectively evaluated for impairment	9,611,096	8,712,079
Loans and Leases Receivable, Gross	9,693,475	8,814,625
Financing Receivable, Acquired Deteriorated Credit Quality	$ 7,316	$ 9,941

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Allowance for loan losses associated with purchased loans with evidence of credit deterioration.

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No definition available.

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Financing Receivable, Acquired Deteriorated Credit Quality

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