Securities (Securities by Contractual Maturity) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Available for sale debt securities maturities within 1 year amortized cost	$ 131,917
Available for sale debt securities maturities 1-5 years amortized cost	164,281
Available for sale debt securities maturities 5-10 years amortized cost	37,965
Available for sale debt securities maturities after 10 years amortized cost	46,831
Available for sale debt securities maturities total amortized cost	380,994
Available for sale debt securities maturities within 1 year weighted average yield	4.25%
Available for sale debt securities maturities 1-5 years weighted average yield	3.77%
Available for sale debt securities maturities 5-10 years weighted average yield	2.65%
Available for sale debt securities maturities after 10 years weighted average yield	1.71%
Available for sale debt securities maturities total weighted average yield	3.57%
Available for sale debt securities maturities within 1 year fair value	133,376
Available for sale debt securities maturities 1-5 years fair value	167,772
Available for sale debt securities maturities 5-10 years fair value	39,432
Available for sale debt securities maturities after 10 years fair value	47,505
Available for sale debt securities fair value	388,085
Held to maturity debt securities maturities total amortized cost	31,264	40,381
Held to maturity debt securities maturities within 1 year fair value	7,151
Held to maturity debt securities maturities 1-5 years fair value	15,810
Held to maturity debt securities maturities 5-10 years fair value	6,860
Held to maturity debt securities maturities after 10 years fair value	2,141
Held to maturity securities fair value	31,962	41,420
Corporate bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available for sale debt securities maturities within 1 year amortized cost	5,027
Available for sale debt securities maturities 1-5 years amortized cost	5,704
Available for sale debt securities maturities 5-10 years amortized cost	402
Available for sale debt securities maturities after 10 years amortized cost	0
Available for sale debt securities maturities total amortized cost	11,133
Available for sale debt securities maturities within 1 year weighted average yield	6.64%
Available for sale debt securities maturities 1-5 years weighted average yield	2.82%
Available for sale debt securities maturities 5-10 years weighted average yield	2.45%
Available for sale debt securities maturities after 10 years weighted average yield	0.00%
Available for sale debt securities maturities total weighted average yield	4.53%
Available for sale debt securities fair value	11,371	14,381
Trust Preferred Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available for sale debt securities maturities within 1 year amortized cost	0
Available for sale debt securities maturities 1-5 years amortized cost	0
Available for sale debt securities maturities 5-10 years amortized cost	0
Available for sale debt securities maturities after 10 years amortized cost	31,969
Available for sale debt securities maturities total amortized cost	31,969
Available for sale debt securities maturities within 1 year weighted average yield	0.00%
Available for sale debt securities maturities 1-5 years weighted average yield	0.00%
Available for sale debt securities maturities 5-10 years weighted average yield	0.00%
Available for sale debt securities maturities after 10 years weighted average yield	1.38%
Available for sale debt securities maturities total weighted average yield	1.38%
States and political subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Available for sale debt securities maturities within 1 year amortized cost	12,296
Available for sale debt securities maturities 1-5 years amortized cost	52,537
Available for sale debt securities maturities 5-10 years amortized cost	0
Available for sale debt securities maturities after 10 years amortized cost	0
Available for sale debt securities maturities total amortized cost	64,833
Available for sale debt securities maturities within 1 year weighted average yield	3.89%
Available for sale debt securities maturities 1-5 years weighted average yield	3.91%
Available for sale debt securities maturities 5-10 years weighted average yield	0.00%
Available for sale debt securities maturities after 10 years weighted average yield	0.00%
Available for sale debt securities maturities total weighted average yield	3.91%
Available for sale debt securities fair value	67,340	72,620
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Available for sale debt securities maturities within 1 year amortized cost	60,133
Available for sale debt securities maturities 1-5 years amortized cost	106,040
Available for sale debt securities maturities 5-10 years amortized cost	37,563
Available for sale debt securities maturities after 10 years amortized cost	14,862
Available for sale debt securities maturities total amortized cost	218,598
Available for sale debt securities maturities within 1 year weighted average yield	4.30%
Available for sale debt securities maturities 1-5 years weighted average yield	3.76%
Available for sale debt securities maturities 5-10 years weighted average yield	2.65%
Available for sale debt securities maturities after 10 years weighted average yield	2.43%
Available for sale debt securities maturities total weighted average yield	3.63%
Available for sale debt securities fair value	228,505	231,233
Held to maturity debt securities maturities within 1 year amortized cost	6,995
Held to maturity debt securities maturities 1-5 years amortized cost	15,465
Held to maturity debt securities maturities 5-10 years amortized cost	6,710
Held to maturity debt securities maturities after 10 years amortized cost	2,094
Held to maturity debt securities maturities total amortized cost	31,264	40,381
Held to maturity debt securities maturities within 1 year weighted average yield	2.57%
Held to maturity debt securities maturities 1-5 years weighted average yield	2.48%
Held to maturity debt securities maturities 5-10 years weighted average yield	2.37%
Held to maturity debt securities maturities after 10 years weighted average yield	0.88%
Held to maturity debt securities maturities total weighted average yield	2.37%
Held to maturity securities fair value	31,962	41,420
Obligations of U.S. government-sponsored enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Available for sale debt securities maturities within 1 year amortized cost	54,461
Available for sale debt securities maturities 1-5 years amortized cost	0
Available for sale debt securities maturities 5-10 years amortized cost	0
Available for sale debt securities maturities after 10 years amortized cost	0
Available for sale debt securities maturities total amortized cost	54,461
Available for sale debt securities maturities within 1 year weighted average yield	4.04%
Available for sale debt securities maturities 1-5 years weighted average yield	0.00%
Available for sale debt securities maturities 5-10 years weighted average yield	0.00%
Available for sale debt securities maturities after 10 years weighted average yield	0.00%
Available for sale debt securities maturities total weighted average yield	4.04%
Available for sale debt securities fair value	$ 55,669	$ 31,670