Deposits (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Contractual Maturities, Time Deposits, $100,000 or More [Abstract]
Three months or less	$ 142,676
After three months through six months	96,075
After six months through twelve months	251,201
After twelve months	533,341
Total	1,023,293
Deposits, by Component, Alternative [Abstract]
Noninterest bearing	1,881,360	1,702,740
Interest-bearing transaction	791,943	732,038
Savings and MMDA	2,700,241	2,262,369
Time deposits	1,701,446	1,738,970
Total deposits	7,074,990	6,436,117
Noninterest bearing transaction, percentage of total deposits	27.00%	26.00%
Interest bearing transactions, percentage of total deposits	11.00%	11.00%
Savings and MMDA, percentage of total deposits	38.00%	36.00%
Time deposits, percentage of total deposits	24.00%	27.00%
Total deposits	100.00%	100.00%
Time Deposits, Rolling Year Maturity [Abstract]
Due within 1 year	875,929
Due in 1 to 2 years	391,309
Due in 2 to 3 years	310,607
Due in 3 to 4 years	41,820
Due in 4 to 5 years	38,724
Due after 5 years	43,057
Total	$ 1,701,446

Interest-bearing Domestic Deposits, Savings and Money Market Deposit Accounts

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Interest-bearing Domestic Deposits, Transaction

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Percentage of Interest-bearing Domestic Savings and MMDA Deposits to Deposits

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Percentage of Interest-bearing Transaction Deposits to Deposits

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Percentage of noninterest-bearing transaction deposits to deposits

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Percent Total Deposits

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The amount of contractual maturities of domestic and foreign time deposits (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $100,000 or more, after twelve months from the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 405

-Section 50

-Paragraph 1

-Subparagraph (a)

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-Name Industry Guide

-Number 3

-Section V

-Paragraph D

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.12)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 9

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Amount of interest-bearing domestic time deposits. Time deposits bear interest for a fixed, stated period of time and include certificate of deposits and individual retirement accounts.

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

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Percentage of interest-bearing domestic time deposit liabilities to total deposit liabilities.

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Amount of time deposits maturing after 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

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

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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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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 time deposits (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $100,000 or more.

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