| **Accumulated Other Comprehensive Income Reclassifications out of Accumulated Other Comprehensive Income (Details) (USD $)In Thousands, unless otherwise specified** | 3 Months Ended | 6 Months Ended |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]**                                                            |           |           |   |   |
| Income tax expense                                                                                                                                                   | $ 236          | $ 236          | $ 259 | $ 2,089 |
| Total, net of tax                                                                                                                                                    | (2,792)        | 3,183          | (4,069) | 7,779 |
| Reclassification out of Accumulated Other Comprehensive Income [Member]                                                                                              |           |           |   |   |
| **Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]**                                                            |           |           |   |   |
| Total, net of tax                                                                                                                                                    | (445)          | (363)          | (445) | (1,955) |
| Unrealized gains (losses) on available for sale securities [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]                        |           |           |   |   |
| **Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]**                                                            |           |           |   |   |
| Net realized gains on sale of securities                                                                                                                             | (720)          | (345)          | (720) | (2,723) |
| Income tax expense                                                                                                                                                   | 275            | 136            | 275 | 1,076 |
| Total, net of tax                                                                                                                                                    | (445)          | (209)          | (445) | (1,647) |
| Defined benefit plan items [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]                                                        |           |           |   |   |
| **Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]**                                                            |           |           |   |   |
| Personnel expense                                                                                                                                                    | 0              | (255)          | 0 | (509) |
| Income tax expense                                                                                                                                                   | 0              | 101            | 0 | 201 |
| Total, net of tax                                                                                                                                                    | $ 0            | $ (154)        | $ 0 | $ (308) |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Other Comprehensive Income (Loss), Reclassification Adjustments from AOCI, Pension and Other Postretirement Benefit Plans, for Gain (Loss), before Tax
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Article 5
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Article 4Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Income Tax Expense (or Benefit) -URI http://asc.fasb.org/extlink&oid=6515339Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319
+ Details**Name:**us-gaap_IncomeTaxExpenseBenefit**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1377-109256
+ Details**Name:**us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**duration |
| X                                                                                                                                                                                                                            |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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