| **Loans and Allowance - Additional Information (Details) (USD $)In Thousands, unless otherwise specified** |         |          | 3 Months Ended | 9 Months Ended |
|------------------------------------------------------------------------------------------------------------|---------|----------|----------------|----------------|
||
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                           |    |     |           |           |
| Residential real estate loans held for sale                                                                | $ 5,312 | $ 22,300 |           |           |
| Percentage of troubled debt restructured loans                                                             |    |     | 67.00%         | 40.00%         |
| Number of troubled debt restructured loans                                                                 |    |     | 5              | 12             |

| X                                                                                                                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Financing Receivable, Modifications, Post-Modification, Loans as Percentage of Troubled Debt Restructured Loans
+ References
No definition available.
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| X                                                                                                                                                                            |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of financing receivables that have been modified by troubled debt restructurings.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953676-111524
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of loans held for sale, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.
+ References
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