Financial Instruments And Investments (Unrecognized Gross Unrealized Gains And The Fair Value) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Financial Instruments and Investments [Line Items]
Fair Value	$ 139,509	$ 111,555
Unrealized Gains	20,124	16,072
Minimum
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Available for Sale Securities, Weighted Average Term	3 years
Maximum
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Available for Sale Securities, Weighted Average Term	7 years
Collateralized Mortgage Backed Securities
Financial Instruments and Investments [Line Items]
Fair Value	25,077	18,472
Unrealized Gains	1,220	793
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Available for Sale Securities, Maturity Term	10 years
U.S. Government Bonds
Financial Instruments and Investments [Line Items]
Fair Value	10,263	10,450
Unrealized Gains	972	183
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Available-for-sale Securities, Debt Securities	12,776
Available-for-sale Securities, Debt Maturities, within One Year, Fair Value	1,316
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Fair Value	1,685
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Fair Value	6,844
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	2,931
Municipal Bonds
Financial Instruments and Investments [Line Items]
Fair Value	30,310	15,633
Unrealized Gains	1,792	592
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Available-for-sale Securities, Debt Securities	37,316
Available-for-sale Securities, Debt Maturities, within One Year, Fair Value	1,009
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Fair Value	12,892
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Fair Value	14,252
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	9,163
Corporate Debt Securities
Financial Instruments and Investments [Line Items]
Fair Value	7,641	7,223
Unrealized Gains	459	362
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Available-for-sale Securities, Debt Securities	12,400
Available-for-sale Securities, Debt Maturities, within One Year, Fair Value	1,368
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Fair Value	3,630
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Fair Value	4,338
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	3,064
Debt Securities
Financial Instruments and Investments [Line Items]
Fair Value	73,291	51,778
Unrealized Gains	4,443	1,930
Equity Securities
Financial Instruments and Investments [Line Items]
Fair Value	62,479	56,770
Unrealized Gains	15,681	14,142
Cash and Cash Equivalents
Financial Instruments and Investments [Line Items]
Fair Value	3,739	3,007
Unrealized Gains	$ 0	$ 0

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