Fair Value Measurements (Contractual Maturities Of Available For Sale Investments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Maturing in one year or less	$ 5,164	$ 4,134
Maturing after one year through three years	12,134	21,089
Maturing after three years	4,024	6,114
Total debt securities - available for sale	21,322	31,337
Other Than Available For Sale Municipal Bonds [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Maturing in one year or less	0	34
Maturing after one year through three years	0	2,215
Maturing after three years	0	0
Total debt securities - available for sale	0	2,249
Municipal Bonds - Available For Sale [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Maturing in one year or less	5,164	4,100
Maturing after one year through three years	12,134	18,874
Maturing after three years	4,024	6,114
Total debt securities - available for sale	$ 21,322	$ 29,088