Fair Value Measurements (Carrying Amounts and Estimated Fair Values of Financial Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013		Dec. 31, 2012
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities	$ 31,264		$ 40,381
Loans, net of allowance of loan losses	2,325,758		2,263,130
Time deposits	817,110		870,232
Federal Home Loan Bank advances	288,485		361,172
Junior subordinated debentures	22,681		32,991
Loan servicing rights reserve	130		165
Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities	31,264		40,381
Loans, net of allowance of loan losses	2,325,758		2,263,130
Loan servicing rights	2,479	[1]	1,110	[2]
Time deposits	817,110		870,232
Federal Home Loan Bank advances	288,485		361,172
Junior subordinated debentures	22,681		32,991
Estimated Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities	31,962		41,420
Loans, net of allowance of loan losses	2,391,266		2,350,153
Loan servicing rights	2,609	[1]	1,275	[2]
Time deposits	824,264		879,705
Federal Home Loan Bank advances	310,158		392,805
Junior subordinated debentures	15,189		23,371
Level 1 [Member] | Estimated Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities	0		0
Loans, net of allowance of loan losses	0		0
Loan servicing rights	0	[1]	0	[2]
Time deposits	0		0
Federal Home Loan Bank advances	0		0
Junior subordinated debentures	0		0
Level 2 [Member] | Estimated Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities	31,962		41,420
Loans, net of allowance of loan losses	0		0
Loan servicing rights	0	[1]	0	[2]
Time deposits	824,264		879,705
Federal Home Loan Bank advances	310,158		392,805
Junior subordinated debentures	15,189		23,371
Level 3 [Member] | Estimated Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities	0		0
Loans, net of allowance of loan losses	2,391,266		2,350,153
Loan servicing rights	2,609	[1]	1,275	[2]
Time deposits	0		0
Federal Home Loan Bank advances	0		0
Junior subordinated debentures	$ 0		$ 0

[1] The carrying value of loan servicing rights is net of $130 thousand in reserves as of September 30, 2013. The estimated fair value does not include such adjustment.

[2] The carrying value of loan servicing rights is net of $165 thousand in reserves as of December 31, 2012. The estimated fair value does not include such adjustment.