Stockholders' Equity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Stockholders' Equity [Abstract]
Preferred stock, shares authorized (in shares)	50,000,000	50,000,000
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Changes in the outstanding shares of Common Stock [Roll Forward]
Common stock outstanding at beginning of year	43,075,410	43,075,410
Common stock repurchased for treasury	(471,808)	0
Issuance of treasury stock	680,000	0
Common stock outstanding at end of year	43,283,602	43,075,410
Changes in the treasury shares of Common Stock [Abstract]
Treasury stock held at beginning of period	3,334,597	3,334,597
Common stock repurchased for treasury	471,808	0
Issuance of treasury stock	(680,000)	0
Tresury stock held at end of period	3,126,405	3,334,597
Common stock reserved for issuance under Company's stock option and other employee benefit plans [Abstract]
Common shares reserved for issuance (in shares)	4,430,000
Stockholder Rights Plan [Abstract]
Dividends declared, number of right per common share	1
Exercise price of rights (in dollars per share)	$ 75.00
Minimum percentage of outstanding common shares to be acquired (in hundredths)	25.00%
Minimum percentage of outstanding common shares for tender offer (in hundredths)	20.00%
Redemption price of rights (in dollars per share)	$ 0.05
Minimum percentage of common shares by a single acquirer or group (in hundredths)	20.00%
Period after accumulation of minimum percentage of common shares to invoke redemption of rights	0 years 0 months 10 days
Common Stock Repurchase Plan [Abstract]
Common shares repurchased to treasury during period (in shares)	471,808	0
Aggregate cost of shares repurchased during period	$ 489	$ 0
Total number of common shares authorized for repurchase (in shares)	10,000,000
Total number of common shares repurchased (in shares)	3,680,000
Total number of common shares that may still be repurchased (in shares)	6,320,000