Loans and reserve for credit losses (Financing Receivable Credit Quality Indicators) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014 Acceptable	Dec. 31, 2013 Acceptable	Jun. 30, 2014 Pass-Watch	Dec. 31, 2013 Pass-Watch	Jun. 30, 2014 Special Mention	Dec. 31, 2013 Special Mention	Jun. 30, 2014 Substandard	Dec. 31, 2013 Substandard	Jun. 30, 2014 Originated Loans		Dec. 31, 2013 Originated Loans		Jun. 30, 2014 Originated Loans Acceptable		Jun. 30, 2014 Originated Loans Pass-Watch		Jun. 30, 2014 Originated Loans Special Mention		Jun. 30, 2014 Originated Loans Substandard		Jun. 30, 2014 Acquired Loans		Jun. 30, 2014 Acquired Loans Acceptable		Jun. 30, 2014 Acquired Loans Pass-Watch		Jun. 30, 2014 Acquired Loans Special Mention		Jun. 30, 2014 Acquired Loans Substandard		May 16, 2014 Acquired Loans Substandard		Jun. 30, 2014 Acquired Covered Loans		Jun. 30, 2014 Acquired Covered Loans Acceptable		Jun. 30, 2014 Acquired Covered Loans Pass-Watch		Jun. 30, 2014 Acquired Covered Loans Special Mention		Jun. 30, 2014 Acquired Covered Loans Substandard		May 16, 2014 Acquired Covered Loans Substandard
Commercial real estate:
Owner occupied	$ 256,062	$ 204,998	$ 211,680	$ 147,865	$ 9,904	$ 19,798	$ 10,753	$ 14,730	$ 23,725	$ 22,605	$ 190,712	[1]	$ 204,998	[1]	$ 152,819	[1]	$ 9,904	[1]	$ 5,267	[1]	$ 22,722	[1]	$ 52,267	[2]	$ 47,566	[2]	$ 0	[2]	$ 4,417	[2]	$ 284	[2]			$ 13,083	[3]	$ 11,295	[3]	$ 0	[3]	$ 1,069	[3]	$ 719	[3]
Non-owner occupied	496,121	347,014	431,765	278,854	22,334	33,827	23,226	24,188	18,796	10,145	365,827	[1]	347,014	[1]	330,458	[1]	12,670	[1]	15,377	[1]	7,322	[1]	110,650	[2]	87,529	[2]	9,298	[2]	7,286	[2]	6,537	[2]			19,644	[3]	13,778	[3]	366	[3]	563	[3]	4,937	[3]
Total commercial real estate loans	752,183	552,012	643,445	426,719	32,238	53,625	33,979	38,918	42,521	32,750	556,539	[1]	552,012	[1]	483,277	[1]	22,574	[1]	20,644	[1]	30,044	[1]	162,917	[2]	135,095	[2]	9,298	[2]	11,703	[2]	6,821	[2]			32,727	[3]	25,073	[3]	366	[3]	1,632	[3]	5,656	[3]
Construction	105,011	52,503	95,313	46,274	6,169	2,772	2,655	2,131	874	1,326	54,320	[1]	52,503	[1]	48,397	[1]	2,865	[1]	2,655	[1]	403	[1]	48,127	[2]	46,916	[2]	792	[2]	0	[2]	419	[2]			2,564	[3]	0	[3]	2,512	[3]	0	[3]	52	[3]
Residential real estate	198,879	101,557	191,864	98,633	2,050	1,570	22	147	4,943	1,207	101,975	[1]	101,557	[1]	99,486	[1]	1,504	[1]	22	[1]	963	[1]	83,776	[2]	81,849	[2]	0	[2]	0	[2]	1,927	[2]			13,128	[3]	10,529	[3]	546	[3]	0	[3]	2,053	[3]
Commercial and industrial	300,733	254,170	273,272	242,053	9,951	3,518	12,788	2,694	4,722	5,905	269,019	[1]	254,170	[1]	243,323	[1]	9,931	[1]	11,697	[1]	4,068	[1]	27,093	[2]	25,885	[2]	20	[2]	1,091	[2]	97	[2]			4,621	[3]	4,064	[3]	0	[3]	0	[3]	557	[3]
Consumer	38,122	35,990	38,022	35,984	0	0	0	0	100	6	34,805	[1]	35,990	[1]	34,786	[1]	0	[1]	0	[1]	19	[1]	2,757	[2]	2,676	[2]	0	[2]	0	[2]	81	[2]			560	[3]	560	[3]	0	[3]	0	[3]	0	[3]
Total loans, Amount	$ 1,394,928	$ 996,232	$ 1,241,916	$ 849,663	$ 50,408	$ 61,485	$ 49,444	$ 43,890	$ 53,160	$ 41,194	$ 1,016,658	[1]	$ 996,232	[1]	$ 909,269	[1]	$ 36,874	[1]	$ 35,018	[1]	$ 35,497	[1]	$ 324,670	[2],[4]	$ 292,421	[2]	$ 10,110	[2]	$ 12,794	[2]	$ 9,345	[2]	$ 17,663	[3]	$ 53,600	[3],[5]	$ 40,226	[3]	$ 3,424	[3]	$ 1,632	[3]			$ 8,318	[3]

[1] Originated loans are loans organically made through the Company's normal and customary origination process

[2] Acquired loans are loans acquired in the acquisition of Home, discussed elsewhere in this report

[3] Acquired covered loans are loans in the Home portfolio that are covered under FDIC loss share agreements

[4] Acquired loans are loans acquired in the acquisition of Home, discussed elsewhere in this report, less acquired covered loans

[5] Acquired covered loans acquired in the acquisition of Home that are covered under FDIC loss share agreements