Fair Value Measurements And Marketable Securities (Schedule Of Fair Value Of Available-For-Sale Securities By Major Security) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items]
Marketable Securities	$ 4,817	$ 2,093
Level 1 [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable Securities	1,333	1,227
Level 2 [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable Securities	3,484	866
Bank Certificates Of Deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable Securities	2,524
Bank Certificates Of Deposit [Member] | Level 2 [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable Securities	2,524
U.S. Government Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable Securities	1,384
U.S. Government Obligations [Member] | Level 1 [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable Securities	880
U.S. Government Obligations [Member] | Level 2 [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable Securities	504
Corporate Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable Securities	453	1,227
Corporate Obligations [Member] | Level 1 [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable Securities	453	1,227
State And Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable Securities	456	866
State And Municipal Bonds [Member] | Level 2 [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable Securities	$ 456	$ 866