Financial Instruments And Investments (Unrecognized Gross Unrealized Gains And The Fair Value) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Financial Instruments and Investments [Line Items]
Available-for-sale Securities, Unrealized Gain Position, Fair Value	$ 167,164	$ 160,692
Available-for-sale Securities, Gross Unrealized Gain	45,483	47,741
Debt Securities
Financial Instruments and Investments [Line Items]
Available-for-sale Securities, Unrealized Gain Position, Fair Value	39,990	34,158
Available-for-sale Securities, Gross Unrealized Gain	1,846	1,515
Collateralized Mortgage Backed Securities
Financial Instruments and Investments [Line Items]
Available-for-sale Securities, Unrealized Gain Position, Fair Value	10,276	9,929
Available-for-sale Securities, Gross Unrealized Gain	489	433
U.S. Government Bonds
Financial Instruments and Investments [Line Items]
Available-for-sale Securities, Unrealized Gain Position, Fair Value	9,719	6,258
Available-for-sale Securities, Gross Unrealized Gain	180	126
Municipal Bonds
Financial Instruments and Investments [Line Items]
Available-for-sale Securities, Unrealized Gain Position, Fair Value	10,237	8,783
Available-for-sale Securities, Gross Unrealized Gain	528	450
Corporate Debt Securities
Financial Instruments and Investments [Line Items]
Available-for-sale Securities, Unrealized Gain Position, Fair Value	9,758	9,188
Available-for-sale Securities, Gross Unrealized Gain	649	506
Equity Securities
Financial Instruments and Investments [Line Items]
Available-for-sale Securities, Unrealized Gain Position, Fair Value	105,835	103,808
Available-for-sale Securities, Gross Unrealized Gain	43,402	43,145
Common Collective Trust - Equity Funds
Financial Instruments and Investments [Line Items]
Available-for-sale Securities, Unrealized Gain Position, Fair Value	16,891	0
Available-for-sale Securities, Gross Unrealized Gain	235	0
Equity Mutual Funds
Financial Instruments and Investments [Line Items]
Available-for-sale Securities, Unrealized Gain Position, Fair Value	0	16,802
Available-for-sale Securities, Gross Unrealized Gain	0	3,081
Cash and Cash Equivalents
Financial Instruments and Investments [Line Items]
Available-for-sale Securities, Unrealized Gain Position, Fair Value	4,448	5,924
Available-for-sale Securities, Gross Unrealized Gain	$ 0	$ 0