Loans and reserve for credit losses (Schedule of Accounts, Notes, Loans and Financing Receivable) (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2014
Dec. 31, 2013
Commercial real estate:    
Owner occupied $ 259,109 $ 204,998
Non-owner occupied 497,543 347,014
Total commercial real estate loans 756,652 552,012
Construction 125,428 52,503
Residential real estate 204,687 101,557
Commercial and industrial 368,475 254,170
Consumer 37,298 35,990
Total loans 1,492,540 996,232
Less:    
Deferred loan fees, net (1,703)  
Reserve for loan losses (22,053) (20,857)
Loans, net 1,468,784 973,618
Owner occupied, Percent 17.40%  
Non-owner occupied, Percent 33.30%  
Total commercial real estate loans, Percent 50.70%  
Construction, Percent 8.40%  
Residential real estate, Percent 13.70%  
Commercial and industrial, Percent 24.70%  
Consumer, Percent 2.50%  
Total loans, percent 100.00%  
Originated Loans, Receivable    
Commercial real estate:    
Owner occupied 198,845 [1] 204,998 [1]
Non-owner occupied 383,287 [1] 347,014 [1]
Total commercial real estate loans 582,132 [1] 552,012 [1]
Construction 100,437 [1] 52,503 [1]
Residential real estate 122,478 [1] 101,557 [1]
Commercial and industrial 342,746 [1] 254,170 [1]
Consumer 34,897 [1] 35,990 [1]
Total loans 1,182,690 [1] 996,232 [1]
Less:    
Deferred loan fees, net (1,703) [1] (1,757) [1]
Reserve for loan losses (22,053) [1] (20,857) [1]
Loans, net 1,158,934 [1] 973,618 [1]
Owner occupied, Percent 16.80% [1] 20.60% [1]
Non-owner occupied, Percent 32.40% [1] 34.80% [1]
Total commercial real estate loans, Percent 49.20% [1] 55.40% [1]
Construction, Percent 8.50% [1] 5.30% [1]
Residential real estate, Percent 10.40% [1] 10.20% [1]
Commercial and industrial, Percent 29.00% [1] 25.50% [1]
Consumer, Percent 2.90% [1] 3.60% [1]
Total loans, percent 100.00% [1] 100.00% [1]
Acquired Loans, Receivable    
Commercial real estate:    
Owner occupied 48,413 [2]  
Non-owner occupied 102,890 [2]  
Total commercial real estate loans 151,303 [2]  
Construction 22,564 [2]  
Residential real estate 71,385 [2]  
Commercial and industrial 22,444 [2]  
Consumer 1,963 [2]  
Total loans 269,659 [2]  
Less:    
Owner occupied, Percent 18.00% [2]  
Non-owner occupied, Percent 38.20% [2]  
Total commercial real estate loans, Percent 56.20% [2]  
Construction, Percent 8.40% [2]  
Residential real estate, Percent 26.50% [2]  
Commercial and industrial, Percent 8.30% [2]  
Consumer, Percent 0.60% [2]  
Total loans, percent 100.00% [2]  
Acquired Covered Loans, Receivable    
Commercial real estate:    
Owner occupied 11,851 [3]  
Non-owner occupied 11,366 [3]  
Total commercial real estate loans 23,217 [3]  
Construction 2,427 [3]  
Residential real estate 10,824 [3]  
Commercial and industrial 3,285 [3]  
Consumer 438 [3]  
Total loans $ 40,191 [3]  
Less:    
Owner occupied, Percent 29.50% [3]  
Non-owner occupied, Percent 28.30% [3]  
Total commercial real estate loans, Percent 57.80% [3]  
Construction, Percent 6.00% [3]  
Residential real estate, Percent 26.90% [3]  
Commercial and industrial, Percent 8.20% [3]  
Consumer, Percent 1.10% [3]  
Total loans, percent 100.00% [3]  
[1] Originated loans are loans organically made through the Company's normal and customary origination
[2] Acquired loans are loans acquired in the acquisition of Home, discussed elsewhere in this report, less acquired covered loans
[3] Acquired covered loans acquired in the acquisition of Home that are covered under FDIC loss share