Business Combination - Schedule of Calculation of Goodwill (Detail) (USD $)
In Thousands, except Share data, unless otherwise specified
12 Months Ended
Dec. 31, 2013
Nov. 01, 2013
Dec. 31, 2012
Purchase Price:      
Union common shares outstanding 2,703,840 2,703,840 1,716,316
Riverview common stock issued 2,703,840 987,524 1,750,003
Purchase price assigned to shares exchanged for stock $ 10,152    
Total Purchase Price 10,153    
Loans:      
Allowance for loan losses 1,427    
Core deposit intangible 1,264    
Premises and equipment 519 1,660  
Reversal of old purchase account marks and deferred fees/costs (142)    
Miscellaneous assets and liabilities (780)    
Deferred tax asset 1,495    
Decrease to reflect liabilities acquired at fair value:      
Time deposits (379)    
Net assets acquired 10,782 (10,782)  
Bargain purchase price gain resulting from consolidation 629    
Interest Rate Fair Value [Member]
     
Loans:      
Loans 268    
General Credit Fair Value Mark [Member]
     
Loans:      
Loans (795)    
Specific Credit Fair Value Mark [Member]
     
Loans:      
Loans (1,705)    
Union Bank [Member]
     
Purchase Price:      
Union common shares outstanding 506,513    
Exchange ratio 1.95 1.95  
Union fractional shares exchanged for cash 176    
Purchase price paid to each Union common share exchanged for cash $ 10.75    
Purchase price assigned to each Union common share exchanged for cash 1    
Net Assets Acquired:      
Union common shareholders' equity $ 9,610    
Riverview Bank [Member]
     
Purchase Price:      
Exchange ratio   1.00  
Riverview common stock issued 987,524    
Fair market value of Riverview common share $ 10.28