Deposits Deposits (Details 1) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Time Deposits Balance [Line Items]
Time Deposit Maturities, Next Twelve Months	$ 1,931,134
Time Deposit Maturities, Year Two	87,275
Time Deposit Maturities, Year Three	20,264
Time Deposit Maturities, Year Four	17,296
Time Deposit Maturities, Year Five	9,220
Time Deposit Maturities, after Year Five	133
Time Deposits	2,065,322	$ 2,172,290
Deposits Exceeding FDIC Insurance Limit of $250,000 [Member]
Time Deposits Balance [Line Items]
Time Deposit Maturities, Next Twelve Months	337,257
Time Deposit Maturities, Year Two	9,870
Time Deposit Maturities, Year Three	3,713
Time Deposit Maturities, Year Four	1,607
Time Deposit Maturities, Year Five	2,895
Time Deposit Maturities, after Year Five	0
Time Deposits	355,342
Deposits FDC Insured $250,000 and Under [Member]
Time Deposits Balance [Line Items]
Time Deposit Maturities, Next Twelve Months	1,593,877
Time Deposit Maturities, Year Two	77,405
Time Deposit Maturities, Year Three	16,551
Time Deposit Maturities, Year Four	15,689
Time Deposit Maturities, Year Five	6,325
Time Deposit Maturities, after Year Five	133
Time Deposits	$ 1,709,980

[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

+ Details

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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

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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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 time deposit liabilities, including certificates of deposit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=50488274&loc=d3e64164-112818

Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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