Consolidated Statements of Comprehensive Income (Parenthetical) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Condensed Consolidated Statements of Comprehensive Income [Abstract]
Unrealized holding (losses) gains arising during period, tax	$ 1,135,000	$ 355,000
Reclassification adjustment for losses included in net income, tax	$ 4,000	$ 2,000