FAIR VALUE DISCLOSURES (Carrying And Fair Value Information) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
Assets [Abstract]
Cash and due from banks	$ 197,538	$ 154,192	$ 199,337
Interest bearing deposits with other banks	148,915	43,777	360,469
Available-for-sale securities	2,016,373	2,082,329	2,194,373
Liabilities [Abstract]
Noninterest bearing deposits	3,103,321	3,031,528	2,914,949
Other time deposits	1,842,869	1,853,491	$ 1,962,138
Carrying Value [Member]
Assets [Abstract]
Cash and due from banks	197,538	154,192
Interest bearing deposits with other banks	148,915	43,777
Available-for-sale securities	2,016,373	2,082,329
Net loans and leases	10,318,191	10,246,320
Loans held for sale	150,046	157,907
Liabilities [Abstract]
Noninterest bearing deposits	3,103,321	3,031,528
Savings and interest bearing deposits	6,540,507	6,446,142
Other time deposits	1,842,869	1,853,491
Federal funds purchased and securities sold under agreement to repurchase and other short-term borrowings	431,093	467,946
Long-term debt and other borrowings	90,879	92,973
Carrying Value [Member] \| Forward Commitments [Member]
Derivative instruments [Abstract]
Derivative liabilities	(1,804)
Derivative assets		109
Carrying Value [Member] \| Commitments To Fund Fixed Rate Mortgage Loans [Member]
Derivative instruments [Abstract]
Derivative assets	6,436	3,390
Carrying Value [Member] \| Interest Rate Swap Position To Receive [Member]
Derivative instruments [Abstract]
Derivative assets	17,043	15,614
Carrying Value [Member] \| Interest Rate Swap Position To Pay [Member]
Derivative instruments [Abstract]
Derivative liabilities	(17,285)	(15,856)
Fair Value [Member]
Assets [Abstract]
Cash and due from banks	197,538	154,192
Interest bearing deposits with other banks	148,915	43,777
Available-for-sale securities	2,016,373	2,082,329
Net loans and leases	10,458,334	10,331,043
Loans held for sale	150,046	157,907
Liabilities [Abstract]
Noninterest bearing deposits	3,103,321	3,031,528
Savings and interest bearing deposits	6,540,507	6,446,142
Other time deposits	1,856,817	1,867,034
Federal funds purchased and securities sold under agreement to repurchase and other short-term borrowings	430,343	467,263
Long-term debt and other borrowings	99,279	98,502
Fair Value [Member] \| Forward Commitments [Member]
Derivative instruments [Abstract]
Derivative liabilities	(1,804)
Derivative assets		109
Fair Value [Member] \| Commitments To Fund Fixed Rate Mortgage Loans [Member]
Derivative instruments [Abstract]
Derivative assets	6,436	3,390
Fair Value [Member] \| Interest Rate Swap Position To Receive [Member]
Derivative instruments [Abstract]
Derivative assets	17,043	15,614
Fair Value [Member] \| Interest Rate Swap Position To Pay [Member]
Derivative instruments [Abstract]
Derivative liabilities	$ (17,285)	$ (15,856)

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Federal Funds Purchased, Securities Loaned Or Sold Under Agreements To Repurchase And Other Short-Term Borrowings Fair Value Disclosure

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This element represents the portion of the balance sheet assertion valued at fair value by the entity for savings and interest bearing deposits held by the company.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

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Amount of deposits that cannot be withdrawn before a set date without penalty or for which notice of withdrawal is required. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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