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Note 7 - Deposits (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2017
Notes Tables |
Scheduled Maturities of Time Deposits [Table Text Block] |
201 8 |  |  | 76,378 |
201 9 |  |  | 30,124 |
2020 |  |  | 2,224 |
2021 |  |  | 2,931 |
202 2 |  |  | 3,227 |
Thereafter |  |  | --- |
Total time deposits |  | $ | 114,884 |

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- Definition Tabular disclosure of maturities of time deposits (including certificates of deposits, individual retirement accounts and open accounts) held by the entity. + References No definition available. + Details
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Namespace Prefix: | nksh_
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- References No definition available. + Details
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Balance Type: | na
Period Type: | duration