Allowance For Loan Losses, Allowance For Losses On Lending-Related Commitments And Impaired Loans (Summary Of Impaired Loans Evaluated For Impairment By Loan Class) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended				12 Months Ended
	Mar. 31, 2013		Mar. 31, 2012		Dec. 31, 2012
Recorded Investment	$ 203,554	[1]	$ 251,963	[1]	$ 204,545	[1]
Unpaid Principal Balance	229,615		273,842		231,340
Related Allowance	14,607		20,989		13,575
Average Recorded Investment	209,208		253,552		222,076
Interest Income Recognized	2,636		3,149		10,819
Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	101,565	[2]	137,805	[2]	89,983	[2]
Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	101,989		114,158		114,562
Commercial Portfolio Segment [Member] | Commercial And Industrial [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	12,827		8,610		11,010
Unpaid Principal Balance	14,544		10,151		12,562
Related Allowance	3,627		3,270		1,982
Average Recorded Investment	13,034		9,121		13,312
Interest Income Recognized	230		145		881
Commercial Portfolio Segment [Member] | Commercial And Industrial [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	13,963		18,105		20,270
Unpaid Principal Balance	17,153		21,708		27,574
Related Allowance	0		0		0
Average Recorded Investment	14,344		16,614		23,877
Interest Income Recognized	226		226		1,259
Commercial Portfolio Segment [Member] | Franchise [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	0		1,792		1,792
Unpaid Principal Balance	0		1,792		1,792
Related Allowance	0		394		1,259
Average Recorded Investment	0		1,792		1,792
Interest Income Recognized	0		31		122
Commercial Portfolio Segment [Member] | Franchise [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	125		0		0
Unpaid Principal Balance	1,544		0		0
Related Allowance	0		0		0
Average Recorded Investment	1,189		0		0
Interest Income Recognized	26		0		0
Commercial Portfolio Segment [Member] | Warehouse Agreement Borrowings [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Commercial Portfolio Segment [Member] | Warehouse Agreement Borrowings [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Commercial Portfolio Segment [Member] | Community Advantage - Homeowners Association [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Commercial Portfolio Segment [Member] | Community Advantage - Homeowners Association [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Commercial Portfolio Segment [Member] | Aircraft [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Commercial Portfolio Segment [Member] | Aircraft [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	0		260		0
Unpaid Principal Balance	0		260		0
Related Allowance	0		0		0
Average Recorded Investment	0		260		0
Interest Income Recognized	0		5		0
Commercial Portfolio Segment [Member] | Asset-Based Lending [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	511		258		511
Unpaid Principal Balance	511		258		511
Related Allowance	55		41		55
Average Recorded Investment	511		266		484
Interest Income Recognized	7		3		26
Commercial Portfolio Segment [Member] | Asset-Based Lending [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	21		133		25
Unpaid Principal Balance	1,358		1,452		1,362
Related Allowance	0		0		0
Average Recorded Investment	23		622		252
Interest Income Recognized	18		19		76
Commercial Portfolio Segment [Member] | Municipal Receivables [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Commercial Portfolio Segment [Member] | Municipal Receivables [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Commercial Portfolio Segment [Member] | Leases [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Commercial Portfolio Segment [Member] | Leases [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Commercial Portfolio Segment [Member] | Other Receivables [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Commercial Portfolio Segment [Member] | Other Receivables [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Commercial Real Estate Portfolio Segment [Member] | Residential Construction [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	1,881		1,807		2,007
Unpaid Principal Balance	2,007		1,882		2,007
Related Allowance	405		390		389
Average Recorded Investment	1,976		1,807		2,007
Interest Income Recognized	23		24		98
Commercial Real Estate Portfolio Segment [Member] | Residential Construction [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	3,208		3,031		4,085
Unpaid Principal Balance	3,579		3,102		4,440
Related Allowance	0		0		0
Average Recorded Investment	3,708		2,847		4,507
Interest Income Recognized	42		27		143
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Construction Financing Receivable [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	8,682		4,632		1,865
Unpaid Principal Balance	8,682		4,632		1,865
Related Allowance	49		989		70
Average Recorded Investment	8,983		4,572		1,865
Interest Income Recognized	86		55		78
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Construction Financing Receivable [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	3,970		9,788		12,263
Unpaid Principal Balance	4,450		9,788		13,395
Related Allowance	0		0		0
Average Recorded Investment	4,016		9,790		13,635
Interest Income Recognized	49		96		540
Commercial Real Estate Portfolio Segment [Member] | Land [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	17,851		49,766		12,184
Unpaid Principal Balance	19,070		53,325		12,860
Related Allowance	2,380		4,785		1,414
Average Recorded Investment	17,861		50,889		12,673
Interest Income Recognized	104		584		483
Commercial Real Estate Portfolio Segment [Member] | Land [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	11,305		14,649		12,163
Unpaid Principal Balance	16,304		16,952		17,141
Related Allowance	0		0		0
Average Recorded Investment	12,048		14,720		14,646
Interest Income Recognized	203		196		906
Commercial Real Estate Portfolio Segment [Member] | Office [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	5,792		7,974		5,829
Unpaid Principal Balance	5,996		8,819		5,887
Related Allowance	659		2,357		622
Average Recorded Investment	5,853		7,857		5,936
Interest Income Recognized	61		123		246
Commercial Real Estate Portfolio Segment [Member] | Office [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	8,283		10,187		8,939
Unpaid Principal Balance	8,357		11,875		9,521
Related Allowance	0		0		0
Average Recorded Investment	8,306		10,499		9,432
Interest Income Recognized	95		128		437
Commercial Real Estate Portfolio Segment [Member] | Industrial [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	4,229		460		1,150
Unpaid Principal Balance	4,286		487		1,200
Related Allowance	1,241		62		224
Average Recorded Investment	4,244		467		1,208
Interest Income Recognized	65		6		75
Commercial Real Estate Portfolio Segment [Member] | Industrial [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	5,541		3,827		3,598
Unpaid Principal Balance	5,653		4,051		3,776
Related Allowance	0		0		0
Average Recorded Investment	5,563		3,848		3,741
Interest Income Recognized	74		49		181
Commercial Real Estate Portfolio Segment [Member] | Retail Site [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	16,734		23,312		13,240
Unpaid Principal Balance	17,316		23,337		13,314
Related Allowance	674		701		343
Average Recorded Investment	16,773		22,861		13,230
Interest Income Recognized	194		244		584
Commercial Real Estate Portfolio Segment [Member] | Retail Site [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	14,483		14,421		18,073
Unpaid Principal Balance	15,095		14,562		18,997
Related Allowance	0		0		0
Average Recorded Investment	14,628		14,535		19,067
Interest Income Recognized	172		191		892
Commercial Real Estate Portfolio Segment [Member] | Multi Family [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	3,966		6,532		3,954
Unpaid Principal Balance	4,063		6,532		3,954
Related Allowance	152		1,504		348
Average Recorded Investment	4,044		6,511		3,972
Interest Income Recognized	42		81		157
Commercial Real Estate Portfolio Segment [Member] | Multi Family [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	2,200		1,916		2,817
Unpaid Principal Balance	4,541		1,916		4,494
Related Allowance	0		0		0
Average Recorded Investment	2,618		1,919		4,120
Interest Income Recognized	54		25		222
Commercial Real Estate Portfolio Segment [Member] | Mixed Use And Other [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	18,910		18,473		22,249
Unpaid Principal Balance	20,337		19,324		23,166
Related Allowance	2,863		2,070		2,989
Average Recorded Investment	19,317		18,452		23,185
Interest Income Recognized	232		224		1,165
Commercial Real Estate Portfolio Segment [Member] | Mixed Use And Other [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	18,168		26,446		15,462
Unpaid Principal Balance	19,483		28,934		17,210
Related Allowance	0		0		0
Average Recorded Investment	18,345		27,202		16,122
Interest Income Recognized	269		374		912
Home Equity [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	5,160		8,409		7,270
Unpaid Principal Balance	5,751		8,976		7,313
Related Allowance	1,748		3,056		2,569
Average Recorded Investment	5,488		8,480		7,282
Interest Income Recognized	57		116		271
Home Equity [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	10,897		6,086		7,320
Unpaid Principal Balance	13,179		7,441		8,758
Related Allowance	0		0		0
Average Recorded Investment	11,395		6,539		8,164
Interest Income Recognized	131		72		376
Residential Real-Estate [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	4,357		5,737		6,420
Unpaid Principal Balance	4,974		6,156		6,931
Related Allowance	598		1,362		1,169
Average Recorded Investment	4,365		5,722		6,424
Interest Income Recognized	49		48		226
Residential Real-Estate [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	8,627		5,054		8,390
Unpaid Principal Balance	9,053		5,818		9,189
Related Allowance	0		0		0
Average Recorded Investment	8,703		5,056		9,069
Interest Income Recognized	94		52		337
Premium Finance Receivable [Member] | Commercial Insurance Loans [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Premium Finance Receivable [Member] | Commercial Insurance Loans [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Premium Finance Receivable [Member] | Life Insurance Loans [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Premium Finance Receivable [Member] | Life Insurance Loans [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Premium Finance Receivable [Member] | Purchased Life Insurance Loans [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Premium Finance Receivable [Member] | Purchased Life Insurance Loans [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized	0		0		0
Indirect Consumer [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	14		29		0
Unpaid Principal Balance	14		29		0
Related Allowance	3		7		0
Average Recorded Investment	13		30		0
Interest Income Recognized	0		1		0
Indirect Consumer [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	44		48		53
Unpaid Principal Balance	54		60		61
Related Allowance	0		0		0
Average Recorded Investment	48		51		65
Interest Income Recognized	1		1		6
Consumer And Other [Member] | Impaired Loans With A Related ASC 310 Allowance Recorded [Member]
Recorded Investment	651		14		502
Unpaid Principal Balance	651		15		502
Related Allowance	153		1		142
Average Recorded Investment	652		15		502
Interest Income Recognized	8		1		26
Consumer And Other [Member] | Impaired Financing Receivables With No Related Allowance [Member]
Recorded Investment	1,154		207		1,104
Unpaid Principal Balance	1,610		208		1,558
Related Allowance	0		0		0
Average Recorded Investment	1,160		208		1,507
Interest Income Recognized	$ 24		$ 2		$ 94

[1] Impaired loans are considered by the Company to be non-accrual loans, restructured loans or loans with principal and/or interest at risk, even if the loan is current with all payments of principal and interest.

[2] These impaired loans require an allowance for loan losses because the estimated fair value of the loans or related collateral is less than the recorded investment in the loans.