Deposits Deposits (Details 1) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Time Deposits Balance [Line Items]
Time Deposit Maturities, Next Twelve Months	$ 1,895,210
Time Deposit Maturities, Year Two	84,515
Time Deposit Maturities, Year Three	17,101
Time Deposit Maturities, Year Four	6,725
Time Deposit Maturities, Year Five	2,087
Time Deposits	2,005,638	$ 2,065,322
Deposits Exceeding FDIC Insurance Limit of $250,000 [Member]
Time Deposits Balance [Line Items]
Time Deposit Maturities, Next Twelve Months	393,110
Time Deposit Maturities, Year Two	16,630
Time Deposit Maturities, Year Three	1,651
Time Deposit Maturities, Year Four	794
Time Deposit Maturities, Year Five	0
Time Deposits	412,185
Deposits FDC Insured $250,000 and Under [Member]
Time Deposits Balance [Line Items]
Time Deposit Maturities, Next Twelve Months	1,502,100
Time Deposit Maturities, Year Two	67,885
Time Deposit Maturities, Year Three	15,450
Time Deposit Maturities, Year Four	5,931
Time Deposit Maturities, Year Five	2,087
Time Deposits	$ 1,593,453

[Line Items] for Time Deposits Balance [Table]

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- Definition

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.

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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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