Stock-Based Compensation (Additional Information For RSU's Under The 2007 Plan) (Details) - 2007 and 2012 Incentive plan - Restricted Stock Units (RSUs) - shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Shares
Restricted Stock Units outstanding, beginning balance (in shares)	446,000	555,000	695,000
Granted (in shares)	187,000	136,000	154,000
Released (in shares)	(230,000)	(235,000)	(284,000)
Forfeited (in shares)	(41,000)	(10,000)	(10,000)
Restricted Stock Units outstanding, ending balance (in shares)	362,000	446,000	555,000
Expected to vest at end of year (in shares)	356,000	440,000	546,000