Deposits Deposits (Details 1) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Time Deposits Balance [Line Items]
Time Deposit Maturities, Next Twelve Months	$ 4,958,460us-gaap_TimeDepositMaturitiesYearOne
Time Deposits, Weighted Average Interest Rate, Maturities Year One	0.72%
Time Deposit Maturities, Year Two	424,658us-gaap_TimeDepositMaturitiesYearTwo
Time Deposits, Weighted Average Interest Rate, Maturities Year Two	1.01%
Time Deposit Maturities, Year Three	68,825us-gaap_TimeDepositMaturitiesYearThree
Time Deposits, Weighted Average Interest Rate, Maturities Year Three	0.84%
Time Deposit Maturities, Year Four	35,339us-gaap_TimeDepositMaturitiesYearFour
Time Deposits, Weighted Average Interest Rate, Maturities Year Four	1.13%
Time Deposit Maturities, Year Five	11,346us-gaap_TimeDepositMaturitiesYearFive
Time Deposits, Weighted Average Interest Rate, Maturities Year Five	1.03%
Time Deposit Maturities, after Year Five	310
Time Deposits, Weighted Average Interest Rate, Maturities Greater than Five Years	0.78%
Time Deposits	5,498,938us-gaap_TimeDeposits	664,371us-gaap_TimeDeposits
Weighted Average Rate Domestic Deposit, Time Deposits	0.75%
Time Deposits Under $100,000
Time Deposits Balance [Line Items]
Time Deposit Maturities, Next Twelve Months	2,233,704
Time Deposit Maturities, Year Two	176,125
Time Deposit Maturities, Year Three	32,047
Time Deposit Maturities, Year Four	20,272
Time Deposit Maturities, Year Five	4,880
Time Deposit Maturities, after Year Five	310
Time Deposits	2,467,338
Time Deposits $100,000 Or More
Time Deposits Balance [Line Items]
Time Deposit Maturities, Next Twelve Months	2,724,756
Time Deposit Maturities, Year Two	248,533
Time Deposit Maturities, Year Three	36,778
Time Deposit Maturities, Year Four	15,067
Time Deposit Maturities, Year Five	6,466
Time Deposit Maturities, after Year Five	0
Time Deposits	$ 3,031,600

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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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.

+ References

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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.

+ References

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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.

+ References

+ Details

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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.

+ References

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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.

+ References

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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.

+ References

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)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 9

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Weighted average interest rate for time deposits held by the entity with maturities greater than five years.

+ References

No definition available.

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Weighted average interest rate for time deposits held by the entity with maturities greater than four years, but five years or less.

+ References

No definition available.

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Weighted average interest rate for time deposits held by the entity with maturities greater than three years, but four years or less.

+ References

No definition available.

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Weighted average interest rate for time deposits held by the entity with maturities of one year or less.

+ References

No definition available.

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Weighted average interest rate for time deposits held by the entity with maturities greater than two years, but three years or less.

+ References

No definition available.

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Weighted average interest rate for time deposits held by the entity with maturities greater than one year, but two years or less.

+ References

No definition available.

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The weighted average interest rate for domestic time deposit liabilities.

+ References

No definition available.

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