Deposits (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Deposits, by Type [Abstract]
Non-interest bearing demand	$ 1,491,683	$ 1,495,309
Interest bearing:
Demand	1,848,806	1,811,905
Savings	1,602,544	1,547,713
Time, $100 and over	492,051	594,712
Time, other	698,666	790,772
Total interest bearing	4,642,067	4,745,102
Total deposits	6,133,750	6,240,411
Time deposits obtained through Certificate of Deposit Account Registry Service (CDARS)	51,526	72,062
Contractual Maturities, Time Deposits, $100,000 or More [Abstract]
2014, Time, $100 and Over	325,162
2015, Time, $100 and Over	77,068
2016, Time, $100 and Over	34,928
2017, Time, $100 and Over	35,652
2018, Time, $100 and Over	19,241
Time Deposits, $100,000 or More	492,051	594,712
Time Deposits, Fiscal Year Maturity [Abstract]
2014, Time	790,643
2015, Time	180,871
2016, Time	82,334
2017, Time	85,051
2018, Time	51,818
Time Deposits	1,190,717
Interest expense, time deposits, $100,000 or more	$ 4,880	$ 6,951	$ 10,377

Contractual Maturities, Time Deposits, $100,000 or More, Next Twelve Months

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Contractual Maturities, Time Deposits, $100,000 or More, Year Five

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Contractual Maturities, Time Deposits, $100,000 or More, Year Four

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Contractual Maturities, Time Deposits, $100,000 or More, Year Three

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Contractual Maturities, Time Deposits, $100,000 or More, Year Two

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Time Deposits Obtained, Certificate of Deposit Account Registry Service

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The amount of money in accounts that may bear interest and that the depositor is entitled to withdraw at any time without prior notice.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

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-Name Regulation S-X (SX)

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-Section 03

-Paragraph 12

-Article 9

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Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs).

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The aggregate of all domestic and foreign interest-bearing deposit liabilities.

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Interest expense incurred on time deposits, including certificates of deposits, of $100,000 or more in domestic offices.

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-SubTopic 225

-Section S99

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-Subparagraph (SX 210.9-04.6)

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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 time deposits maturing in the fifth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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-Publisher FASB

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-Topic 470

-SubTopic 10

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Amount of time deposits maturing in the fourth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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Amount of time deposits maturing in the next fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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Amount of time deposits maturing in the third fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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Amount of time deposits maturing in the second fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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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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The aggregate amount of domestic and foreign time deposit liabilities (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $100,000 or more.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 405

-Section 50

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-Paragraph A

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The aggregate amount of domestic or foreign time deposits (including certificates of deposits, individual retirement accounts and open accounts) that total to less than $100,000.

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