Deposits Deposits (Details 1) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Time Deposits Balance [Line Items]
Time Deposit Maturities, Next Twelve Months	$ 1,974,912
Time Deposits, Weighted Average Interest Rate, Maturities Year One	0.38%
Time Deposit Maturities, Year Two	$ 140,148
Time Deposits, Weighted Average Interest Rate, Maturities Year Two	0.69%
Time Deposit Maturities, Year Three	$ 33,787
Time Deposits, Weighted Average Interest Rate, Maturities Year Three	0.60%
Time Deposit Maturities, Year Four	$ 5,495
Time Deposits, Weighted Average Interest Rate, Maturities Year Four	0.79%
Time Deposit Maturities, Year Five	$ 17,920
Time Deposits, Weighted Average Interest Rate, Maturities Year Five	0.75%
Time Deposit Maturities, after Year Five	$ 28
Time Deposits, Weighted Average Interest Rate, Maturities Greater than Five Years	0.72%
Time Deposits	$ 2,172,290	$ 4,152,356
Weighted Average Rate Domestic Deposit, Time Deposits	0.41%
Time Deposits Under $100,000
Time Deposits Balance [Line Items]
Time Deposit Maturities, Next Twelve Months	$ 927,447
Time Deposit Maturities, Year Two	65,567
Time Deposit Maturities, Year Three	14,716
Time Deposit Maturities, Year Four	3,049
Time Deposit Maturities, Year Five	8,042
Time Deposit Maturities, after Year Five	28
Time Deposits	1,018,849
Time Deposits $100,000 Or More
Time Deposits Balance [Line Items]
Time Deposit Maturities, Next Twelve Months	1,047,465
Time Deposit Maturities, Year Two	74,581
Time Deposit Maturities, Year Three	19,071
Time Deposit Maturities, Year Four	2,446
Time Deposit Maturities, Year Five	9,878
Time Deposit Maturities, after Year Five	0
Time Deposits	$ 1,153,441

[Line Items] for Time Deposits Balance [Table]

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- Definition

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. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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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. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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

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

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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.

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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.

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

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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.

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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.

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The weighted average interest rate for domestic time deposit liabilities.

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