Loans Loans (Schedule of Acquired Loans) (Details) - HIghland County Bankshares Inc and Subsidiary First and Citizens Bank [Member] $ in Thousands	Mar. 31, 2017 USD ($)
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loans Total Outstanding Balance	$ 51,629
Acquired Loans Carrying Value	50,879
Commercial Portfolio Segment [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loans Carrying Value	3,095
Owner Occupied [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loans Carrying Value	3,054
Non-Owner Occupied [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loans Carrying Value	1,118
Land and Land Improvements [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loans Carrying Value	3,608
Non-Jumbo [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loans Carrying Value	32,035
Jumbo [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loans Carrying Value	4,261
Consumer Portfolio Segment [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loans Carrying Value	3,708
Purchased Impaired Loans [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance	2,456
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Carrying Amount, Net	2,012
Purchased Impaired Loans [Member] | Commercial Portfolio Segment [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Carrying Amount, Net	0
Purchased Impaired Loans [Member] | Owner Occupied [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Carrying Amount, Net	0
Purchased Impaired Loans [Member] | Non-Owner Occupied [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Carrying Amount, Net	0
Purchased Impaired Loans [Member] | Land and Land Improvements [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Carrying Amount, Net	0
Purchased Impaired Loans [Member] | Non-Jumbo [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Carrying Amount, Net	998
Purchased Impaired Loans [Member] | Jumbo [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Carrying Amount, Net	1,014
Purchased Impaired Loans [Member] | Consumer Portfolio Segment [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Carrying Amount, Net	0
Purchase Nonimpaired Loans [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loans Purchase Performing Outstanding Balance	49,173
Acquired Loans Purchased Performing Carrying Value	48,867
Purchase Nonimpaired Loans [Member] | Commercial Portfolio Segment [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loans Purchased Performing Carrying Value	3,095
Purchase Nonimpaired Loans [Member] | Owner Occupied [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loans Purchased Performing Carrying Value	3,054
Purchase Nonimpaired Loans [Member] | Non-Owner Occupied [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loans Purchased Performing Carrying Value	1,118
Purchase Nonimpaired Loans [Member] | Land and Land Improvements [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loans Purchased Performing Carrying Value	3,608
Purchase Nonimpaired Loans [Member] | Non-Jumbo [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loans Purchased Performing Carrying Value	31,037
Purchase Nonimpaired Loans [Member] | Jumbo [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loans Purchased Performing Carrying Value	3,247
Purchase Nonimpaired Loans [Member] | Consumer Portfolio Segment [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Acquired Loans Purchased Performing Carrying Value	$ 3,708