FAIR VALUE DISCLOSURES (Details) (USD $) In Thousands	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Fair Value, Measurements, Recurring [Member]
Available-for-sale securities:
Loans held for sale	$ 0	$ 0
Impaired loans	(46,810)	(40,721)
Other real estate owned	(12,860)	(7,148)
Fair Value, Measurements, Recurring [Member] \| Level 1 [Member]
Available-for-sale securities:
U.S. Government agencies	0	0
Government agency issued residential mortgage-backed securities	0	0
Government agency issued commercial mortgage-backed securities	0	0
Obligations of states and political subdivisions	0	0
Collateralized debt obligations		0
Other	703	437
Mortgage servicing rights	0	0
Derivative instruments	0	0
Loans held for sale	0	0
Impaired loans	0	0
Other real estate owned	0	0
Total	703	437
Liabilities:
Derivative instruments	0	0
Fair Value, Measurements, Recurring [Member] \| Level 2 [Member]
Available-for-sale securities:
U.S. Government agencies	1,599,231	492,175
Government agency issued residential mortgage-backed securities	430,402	319,918
Government agency issued commercial mortgage-backed securities	31,627	23,703
Obligations of states and political subdivisions	486,653	110,244
Collateralized debt obligations	0	0
Other	12,208	15,403
Mortgage servicing rights	0	0
Derivative instruments	0	0
Loans held for sale	70,519	95,987
Impaired loans	0	0
Other real estate owned	0	0
Total	2,560,121	961,443
Liabilities:
Derivative instruments	0	0
Fair Value, Measurements, Recurring [Member] \| Level 3 [Member]
Available-for-sale securities:
U.S. Government agencies	0	0
Government agency issued residential mortgage-backed securities	0	0
Government agency issued commercial mortgage-backed securities	0	0
Obligations of states and political subdivisions	0	0
Collateralized debt obligations		812
Other	0	0
Mortgage servicing rights	39,455	29,363
Derivative instruments	40,338	46,083
Loans held for sale	0	0
Impaired loans	303,657	188,291
Other real estate owned	151,204	67,560
Total	79,793	76,258
Liabilities:
Derivative instruments	39,931	46,231
Mortgage Servicing Rights [Member]
Changes in fair value of net assets (liabilities) classified as Level 3 [Roll Forward]
Beginning Balance	38,642	35,560
Year to date net gains (losses) included in:
Net income (loss)	813	(6,197)
Other comprehensive income	0	0
Purchases, sales, issuances and settlements, net	0	0
Transfers in and/or out of Level 3	0	0
Ending Balance	39,455	29,363
Net unrealized (losses) gains included in net income for the quarter relating to assets and liabilities held	3,839	(8,315)
Derivative Instruments, Net [Member]
Changes in fair value of net assets (liabilities) classified as Level 3 [Roll Forward]
Beginning Balance	2,685	844
Year to date net gains (losses) included in:
Net income (loss)	(2,278)	(992)
Other comprehensive income	0	0
Purchases, sales, issuances and settlements, net	0	0
Transfers in and/or out of Level 3	0	0
Ending Balance	407	(148)
Net unrealized (losses) gains included in net income for the quarter relating to assets and liabilities held	53	(726)
Available-for-sale Securities [Member]
Changes in fair value of net assets (liabilities) classified as Level 3 [Roll Forward]
Beginning Balance	0	2,125
Year to date net gains (losses) included in:
Net income (loss)	0	(1,313)
Other comprehensive income	0	0
Purchases, sales, issuances and settlements, net	0	0
Transfers in and/or out of Level 3	0	0
Ending Balance	0	812
Net unrealized (losses) gains included in net income for the quarter relating to assets and liabilities held	$ 0	$ 0

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This element represents purchases, sales, issuances, and settlements (net) which have taken place during the period in relation to net assets (liabilities) measured at fair value on a recurring basis using unobservable inputs (Level 3).

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This element represents [net] transfers in to and out of net assets (liabilities) measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

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This element represents a net asset (liability) measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

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This item represents the amount of the total change in unrealized (holding) gains or losses for the period which are included in the statement of income (or changes in net assets) in trading revenue. Such unrealized (holding) gains or losses relate to those net assets (liabilities) still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity for Government agency issued commercial mortgage-backed available-for-sale securities.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity for Government agency issued residential mortgage-backed available-for-sale securities.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity for impaired loans.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity for obligations of states and political subdivisions available-for-sale securities.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity for other available-for-sale securities, not otherwise specified.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity for other real estate owned.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity for U.S. Government agencies available-for-sale securities.

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- Definition

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

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- Definition

Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements.

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- Definition

Derivative instrument obligations meeting the definition of a liability which the Company is a party to as of the balance sheet date.

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This item represents the amount of the total realized and unrealized gains or losses for the period which are included in the statement of income (or changes in net assets); the fair value of which assets and liabilities was or is measured on a recurring basis using significant unobservable inputs (Level 3).

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- Definition

This element represents total gains (losses) for the period (realized and unrealized), arising from assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in other comprehensive income (a separate component of shareholders' equity).

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity 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. This item represents loans held-for-sale as presented on the statement of financial position which may include mortgage loans held-for-sale, finance receivables held-for-sale, or any other loans classified as held-for-sale which are due the Company as of the balance sheet date.

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- Definition

Fair value as of the balance sheet date of an asset representing net future revenues from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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