Business Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Business Segments [Abstract]
Number of operating segments									3
Revenues:
Interest income	$ 19,605	$ 19,505	$ 19,098	$ 18,756	$ 18,871	$ 18,918	$ 18,369	$ 17,632	$ 76,964	$ 73,790	$ 69,848
Gains on sales of loans									20,572	16,094	18,564
Other noninterest income									12,930	10,952	11,136
Total operating income (loss)									110,466	100,836	99,548
Expenses:
Provision for loan losses									12,405	14,160	14,959
Interest expense									10,111	11,881	13,235
Salaries and employee benefits									40,693	34,317	34,889
Other noninterest expenses									23,229	21,767	25,406
Total operating expenses									86,438	82,125	88,489
Income before income taxes	5,654	6,712	6,144	5,518	4,926	5,129	4,400	4,256	24,028	18,711	11,059
Income tax expense (benefit)									7,646	5,735	2,949
Net income (loss)									16,382	12,976	8,110
Total assets	977,018				928,124				977,018	928,124	904,137
Goodwill	10,724				10,724				10,724	10,724	10,724
Capital expenditures									1,190	1,844	1,875
Fixed interest rates, minimum, intersegment loans from Retail Banking segment (in hundredths)									3.80%
Fixed interest rates, maximum, intersegment loans from Retail Banking segment (in hundredths)									8.00%
Retail Banking [Member]
Revenues:
Interest income									32,301	32,715	33,922
Gains on sales of loans									0	0	0
Other noninterest income									6,124	5,957	6,093
Total operating income (loss)									38,425	38,672	40,015
Expenses:
Provision for loan losses									2,400	6,000	6,500
Interest expense									7,404	9,154	10,452
Salaries and employee benefits									15,562	14,722	14,661
Other noninterest expenses									12,385	12,026	13,112
Total operating expenses									37,751	41,902	44,725
Income before income taxes									674	(3,230)	(4,710)
Income tax expense (benefit)									(1,479)	(2,798)	(3,216)
Net income (loss)									2,153	(432)	(1,494)
Total assets	813,817				772,552				813,817	772,552	756,250
Goodwill	0				0				0	0	0
Capital expenditures									739	957	1,333
Mortgage Banking [Member]
Revenues:
Interest income									2,358	1,673	2,210
Gains on sales of loans									20,572	16,094	18,567
Other noninterest income									4,315	2,931	3,265
Total operating income (loss)									27,245	20,698	24,042
Expenses:
Provision for loan losses									165	360	34
Interest expense									483	256	365
Salaries and employee benefits									16,675	12,044	13,448
Other noninterest expenses									6,265	5,747	8,892
Total operating expenses									23,588	18,407	22,739
Income before income taxes									3,657	2,291	1,303
Income tax expense (benefit)									1,466	960	521
Net income (loss)									2,191	1,331	782
Total assets	86,978				82,312				86,978	82,312	78,550
Goodwill	0				0				0	0	0
Capital expenditures									272	98	411
Variable rate basis, intersegment loans from Retail Banking segment									The Retail Banking segment charges the Mortgage Banking segment interest at the daily FHLB advance rate plus 50 basis points.
Debt Instrument, Basis Spread on Variable Rate	0.50%								0.50%
Consumer Finance [Member]
Revenues:
Interest income									47,403	43,776	37,382
Gains on sales of loans									0	0	0
Other noninterest income									1,149	855	689
Total operating income (loss)									48,552	44,631	38,071
Expenses:
Provision for loan losses									9,840	7,800	8,425
Interest expense									6,334	5,833	5,278
Salaries and employee benefits									7,591	6,712	6,062
Other noninterest expenses									4,100	3,560	2,893
Total operating expenses									27,865	23,905	22,658
Income before income taxes									20,687	20,726	15,413
Income tax expense (benefit)									8,042	8,116	6,011
Net income (loss)									12,645	12,610	9,402
Total assets	280,205				249,671				280,205	249,671	224,233
Goodwill	10,724				10,724				10,724	10,724	10,724
Capital expenditures									179	786	131
Variable rate basis, intersegment loans from Retail Banking segment									one-month LIBOR plus 200 basis points and fixed rate loans that carry interest rates ranging from 3.8 percent to 8.0 percent.
Debt Instrument, Basis Spread on Variable Rate	2.00%								2.00%
Other [Member]
Revenues:
Interest income									0	0	184
Gains on sales of loans									0	0	0
Other noninterest income									1,322	1,209	1,089
Total operating income (loss)									1,322	1,209	1,273
Expenses:
Provision for loan losses									0	0	0
Interest expense									988	1,014	1,031
Salaries and employee benefits									865	839	717
Other noninterest expenses									479	434	509
Total operating expenses									2,332	2,287	2,257
Income before income taxes									(1,010)	(1,078)	(984)
Income tax expense (benefit)									(383)	(544)	(380)
Net income (loss)									(627)	(534)	(604)
Total assets	3,570				3,262				3,570	3,262	2,840
Goodwill	0				0				0	0	0
Capital expenditures									0	3	0
Eliminations [Member]
Revenues:
Interest income									(5,098)	(4,374)	(3,850)
Gains on sales of loans									0	0	(3)
Other noninterest income									20	0	0
Total operating income (loss)									(5,078)	(4,374)	(3,853)
Expenses:
Provision for loan losses									0	0	0
Interest expense									(5,098)	(4,376)	(3,891)
Salaries and employee benefits									0	0	1
Other noninterest expenses									0	0	0
Total operating expenses									(5,098)	(4,376)	(3,890)
Income before income taxes									20	2	37
Income tax expense (benefit)									0	1	13
Net income (loss)									20	1	24
Total assets	(207,552)				(179,673)				(207,552)	(179,673)	(157,736)
Goodwill	0				0				0	0	0
Capital expenditures									$ 0	$ 0	$ 0