XML 67 R5.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Consolidated Statements of Income (Unaudited) (Parentheticals) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2014 | Jun. 30, 2013 | Jun. 30, 2014 | Jun. 30, 2013
Threshold limit of time deposits, minimum | $ 100 | $ 100 | $ 100 | $ 100

X
- Definition Represents minimum threshold limit of time deposit for which interest to be recognized separately. + References No definition available. + Details
Name: | nksh_MinimumThresholdLimitOfTimeDeposits
Namespace Prefix: | nksh_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration