Stockholders' Equity (Details 2) (USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended	3 Months Ended		12 Months Ended
	Oct. 23, 2012	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Oct. 23, 2002
Stockholders' Equity
Number of shares of outstanding common stock authorized to be repurchased					3,000,000
Expiration date	0 years
Purchases made pursuant to repurchase authorization (in shares)		0		0
Number of remaining shares of common stock authorized to be repurchased		1,653,333
Number of common stock shares purchased and retired		61,869	49,590
Amount of common stock purchased and retired		$ 144	$ 107