Investments (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Schedule of Cost-method Investments [Line Items]
Net gain on sale of securities	$ 794,000	$ 131,000	$ 349,000
Held-to-maturity Securities
Schedule of Cost-method Investments [Line Items]
Security sold	1,200,000
Net gain on sale of securities	$ 122,000