CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Issuance of treasury stock upon exercise of employee stock options, shares	787	65
Cash dividends, per share	$ 0.25	$ 0.24