ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY INFORMATION (Commercial Credit Exposure Credit Risk Profile By Internally Assigned Risk Rating) (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012		Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	$ 2,164,028		$ 2,188,409
Commercial Loans	100.00%		100.00%
Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	812,001		1,459,456
Owner Occupied Commercial (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	636,984	[1]		[1]
Commercial Mortgages (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	618,867		622,799
Construction (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	96,176		106,154
Total Special Mention And Substandard (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	274,858		347,369
Commercial Loans	13.00%		16.00%
Total Special Mention And Substandard (Member) | Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	106,142		216,937
Total Special Mention And Substandard (Member) | Owner Occupied Commercial (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	95,918	[1]		[1]
Total Special Mention And Substandard (Member) | Commercial Mortgages (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	53,694		79,522
Total Special Mention And Substandard (Member) | Construction (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	19,104		50,910
Pass [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	1,889,170		1,841,040
Commercial Loans	87.00%		84.00%
Pass [Member] | Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	705,859		1,242,519
Pass [Member] | Owner Occupied Commercial (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	541,066	[1]		[1]
Pass [Member] | Commercial Mortgages (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	565,173		543,277
Pass [Member] | Construction (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	77,072		55,244
Special Mention [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	73,337		145,639
Special Mention [Member] | Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	18,236		85,848
Special Mention [Member] | Owner Occupied Commercial (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	21,243	[1]		[1]
Special Mention [Member] | Commercial Mortgages (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	31,649		50,044
Special Mention [Member] | Construction (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	2,209		9,747
Accrual [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	168,646		140,599
Accrual [Member] | Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	83,886		107,896
Accrual [Member] | Owner Occupied Commercial (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	56,695	[1]		[1]
Accrual [Member] | Commercial Mortgages (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	16,826		13,664
Accrual [Member] | Construction (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	11,239		19,039
Non Accrual [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	29,063		61,131
Non Accrual [Member] | Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	3,277		23,193
Non Accrual [Member] | Owner Occupied Commercial (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	17,935	[1]		[1]
Non Accrual [Member] | Commercial Mortgages (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	4,268		15,814
Non Accrual [Member] | Construction (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	3,583		22,124
Doubtful/Nonaccrual [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	3,812
Doubtful/Nonaccrual [Member] | Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	743
Doubtful/Nonaccrual [Member] | Owner Occupied Commercial (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	45	[1]		[1]
Doubtful/Nonaccrual [Member] | Commercial Mortgages (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	951
Doubtful/Nonaccrual [Member] | Construction (Member)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial Loans	$ 2,073

[1] Prior to 2012, owner occupied commercial loans were included in commercial loan balances.