Fair Value Of Financial Instruments (Estimated Fair Values And Carrying Amounts Of Financial Instruments) (Details) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2010	Dec. 31, 2009
Cash and cash equivalents	$ 261,804	$ 337,778	$ 1,124,736	$ 175,397
FDIC loss share receivable	670,465	726,871
Derivative instruments	40,683
Deposits	9,073,522	7,915,106
Short-term borrowings	215,778	220,328
Long-term debt	463,016	432,251
Derivative instruments	26,909
Carrying Amount [Member]
Cash and cash equivalents	261,804	337,778
Investment securities	2,215,361	2,019,814
Loans and loans held for sale	7,276,261	6,119,237
FDIC loss share receivable	670,465	726,871
Derivative instruments	40,683	37,320
Accrued interest receivable	38,125	34,250
Deposits	9,073,522	7,915,106
Short-term borrowings	215,778	220,328
Long-term debt	463,016	432,251
Derivative instruments	26,909	22,904
Accrued interest payable	7,880	8,583
Fair Value [Member]
Cash and cash equivalents	261,804	337,778
Investment securities	2,219,641	2,021,788
Loans and loans held for sale	7,424,182	6,362,961
FDIC loss share receivable	382,909	392,484
Derivative instruments	40,683	37,320
Accrued interest receivable	38,128	34,250
Deposits	8,955,619	7,764,569
Short-term borrowings	215,778	220,328
Long-term debt	459,329	441,902
Derivative instruments	26,909	22,904
Accrued interest payable	$ 7,880	$ 8,583

Estimated discounted fair value of total un-submitted reimbursable losses from the FDIC on assets covered by loss share agreements, at the end of the period

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Loans And Loans Held For Sale

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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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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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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Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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