Securities (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 security security_type transfer	Sep. 30, 2012
Investment Securities [Line Items]
Number of securities sold			21
Proceeds from sale of securities			$ 89,900,000
Available-for-sale Securities, Gross Realized Losses		37,000
Proceeds from sale of available-for-sale securities		3,200,000	76,262,000	252,563,000
Held to maturity securities, ratio of remaining par value to original purchases par value				15.00%
Investment securities, value called by issuing agency				160,300,000
Net security gains realized	0	(37,000)	21,000	959,000
Number of securities, type			2
Transfers of securities between AFS and HTM portfolios, number			0
Securities pledged to secure public deposits and other	709,300,000		709,300,000
Held-to-maturity Securities [Member]
Investment Securities [Line Items]
Number of securities sold			5
Mortgage Backed Securities, Other [Member]
Investment Securities [Line Items]
Number of securities sold				4
Number of securities, type			9
Collateralized mortgage obligations [Member]
Investment Securities [Line Items]
Proceeds from sale of available-for-sale securities				257,400,000
Number of securities, type			30
Agency CMOs [Member]
Investment Securities [Line Items]
Number of securities sold				27
Government Agency Debentures [Member]
Investment Securities [Line Items]
Number of securities, type			11
Private-Label Collateralized Mortgage Obligations [Member]
Investment Securities [Line Items]
Number of securities sold		2		7
Bonds [Member]
Investment Securities [Line Items]
Number of securities sold				5
Bonds [Member] | Held-to-maturity Securities [Member]
Investment Securities [Line Items]
Number of securities sold			1
Agency Debentures [Member]
Investment Securities [Line Items]
Investment securities, value called by issuing agency		25,000,000	50,000,000
Number of securities, type				11
Number of securities called	0
Corporate debt securities [Member]
Investment Securities [Line Items]
Investment securities, value called by issuing agency		$ 5,000,000
Number of securities called				1
Amortizing Securities, Returned At Least 85% of Principal [Member] | Held-to-maturity Securities [Member]
Investment Securities [Line Items]
Number of securities sold			4
Investment securities, return on principal, percentage (at least)			85.00%
Municipal Bonds [Member]
Investment Securities [Line Items]
Number of securities, type			26