Long-term Borrowings (Details) - USD ($)	9 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Long term advances with federal home loan bank [Abstract]
Percentage of entity's assets equal to line of credit facility	30.00%
Collateral pledged under blanket floating lien agreement	$ 754,944,000
Long-term federal home loan bank advances	0	$ 0
Public deposit accounts	219,291,000
Outstanding letters of credit	190,000,000
US government and agency securities
Long term advances with federal home loan bank [Abstract]
Outstanding letters of credit	$ 74,426,000

Refers to the percentage of company's assets equal to line of credit facility with federal home loan bank.

No definition available.

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- Definition

Public deposit means to accept fund from public in the form of deposit.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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- Definition

Amount of securities, mortgage loans, or other financial instruments pledged as collateral for deposits.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116652737&loc=d3e64164-112818

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- Definition

Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Section 45
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-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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