Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014
Stockholders' Equity [Abstract]
Common 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, shares issued (in shares)			46,410,000	46,410,000
Common stock, shares outstanding (in shares)	40,738,000	40,738,000	40,738,000	40,738,000
Preferred stock, par value (in dollars per share)			$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)			50,000,000	50,000,000
Preferred stock, shares issued (in shares)			0	0
Preferred stock, shares outstanding (in shares)			0	0
Changes in the outstanding shares of Common Stock [Roll Forward]
Common stock outstanding at beginning of year (in shares)	40,738,000	41,176,000
Common stock repurchased for treasury (in shares)	0	(438,000)
Issuance of treasury stock (in shares)	0	0
Common stock outstanding at end of year (in shares)	40,738,000	40,738,000
Changes in the treasury shares of Common Stock [Abstract]
Treasury stock held at beginning of period (in shares)	5,672,000	5,234,000
Common stock repurchased for treasury (in shares)	0	438,000
Issuance of treasury stock (in shares)	0	0
Treasury stock held at end of period (in shares)	5,672,000	5,672,000
Common Stock Repurchase Plan [Abstract]
Common shares repurchased to treasury during period (in shares)	0	438,000
Aggregate cost of shares repurchased during period	$ 0	$ 525
Total number of common shares authorized for repurchase (in shares)			10,000,000
Total number of common shares repurchased (in shares)			6,226,000
Total number of common shares that may still be repurchased (in shares)			3,774,000
Common stock reserved for issuance under Company's stock option and other employee benefit plans [Abstract]
1993 Srock Incentive Plan			4,320,000
Other employee benefit plan			110,000
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
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	10 days