Employee Benefit Plans (Schedule Of Allocation Of Plan Assets) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011		Dec. 31, 2010
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 285,074		$ 247,713
U.S. Small-Cap [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	11,178	[1]	10,647	[1]
U.S. Mid-Cap [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	50,264	[1]	46,851	[1]
U.S. Large-Cap [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	91,561	[1]	77,632	[1]
Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	22,509	[1]	24,995	[1]
U.S. Government Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13,454	[2]	3,053	[2]
State And Local Government Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	18,416	[3]	13,679	[3]
Non-U.S. Government Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,968	[4]	3,469	[4]
U.S. Government Asset And Mortgage Backed Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	800	[5]	1,073	[5]
Other Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	51,470	[6]	45,628	[6]
Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8,029	[7]	6,110	[7]
Other Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	421	[8]	839	[8]
Corporate fixed income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14,004	[9]	13,737	[9]
Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	92,210		72,699
Level 1 [Member] | U.S. Small-Cap [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	11,178	[1]	10,647	[1]
Level 1 [Member] | U.S. Mid-Cap [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	23,474	[1]	21,163	[1]
Level 1 [Member] | U.S. Large-Cap [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	44,820	[1]	38,397	[1]
Level 1 [Member] | U.S. Government Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12,738	[2]	2,492	[2]
Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	192,864		175,014
Level 2 [Member] | U.S. Mid-Cap [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	26,790	[1]	25,688	[1]
Level 2 [Member] | U.S. Large-Cap [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	46,741	[1]	39,235	[1]
Level 2 [Member] | Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	22,509	[1]	24,995	[1]
Level 2 [Member] | U.S. Government Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	716	[2]	561	[2]
Level 2 [Member] | State And Local Government Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	18,416	[3]	13,679	[3]
Level 2 [Member] | Non-U.S. Government Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,968	[4]	3,469	[4]
Level 2 [Member] | U.S. Government Asset And Mortgage Backed Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	800	[5]	1,073	[5]
Level 2 [Member] | Other Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	51,470	[6]	45,628	[6]
Level 2 [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8,029	[7]	6,110	[7]
Level 2 [Member] | Other Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	421	[8]	839	[8]
Level 2 [Member] | Corporate fixed income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14,004	[9]	13,737	[9]
Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets
Level 3 [Member] | U.S. Small-Cap [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		[1]		[1]
Level 3 [Member] | U.S. Mid-Cap [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		[1]		[1]
Level 3 [Member] | U.S. Large-Cap [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		[1]		[1]
Level 3 [Member] | Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		[1]		[1]
Level 3 [Member] | U.S. Government Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		[2]		[2]
Level 3 [Member] | State And Local Government Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		[3]		[3]
Level 3 [Member] | Non-U.S. Government Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		[4]		[4]
Level 3 [Member] | U.S. Government Asset And Mortgage Backed Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		[5]		[5]
Level 3 [Member] | Other Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		[6]		[6]
Level 3 [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		[7]		[7]
Level 3 [Member] | Other Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		[8]		[8]
Level 3 [Member] | Corporate fixed income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		[9]		[9]

[1] Equity securities includes investments in 1) common stock, 2) preferred stock and 3) mutual funds. Investments in common and preferred stocks are valued using quoted market prices multiplied by the number of shares owned. Investments in mutual funds are valued at the net asset value per share multiplied by the number of shares held as of the measurement date and are traded on listed exchanges.

[2] U.S. government securities includes agency and treasury debt. These investments are valued using dealer quotes in an active market.

[3] State and local government securities include different U.S. state and local municipal bonds and asset backed securities, these investments are valued utilizing a market approach that includes various valuation techniques and sources such as value generation models, broker quotes, benchmark yields and securities, reported trades, issuer trades and/or other applicable data.

[4] Non-U.S. government securities includes debt securities issued by foreign governments and are valued utilizing a price spread basis valuation technique with observable sources from investment dealers and research vendors.

[5] U.S. government asset and mortgage backed securities includes government-backed mortgage funds which are valued utilizing an income approach that includes various valuation techniques and sources such as discounted cash flows models, benchmark yields and securities, reported trades, issuer trades and/or other applicable data.

[6] Other fixed income investments are actively managed fixed income vehicles that are valued at the net asset value per share multiplied by the number of shares held as of the measurement date.

[7] Short-term investments include governmental agency funds, government repurchase agreements, commingled funds, and pooled funds and mutual funds. Governmental agency funds are valued utilizing an option adjusted spread valuation technique and sources such as interest rate generation processes, benchmark yields and broker quotes. Investments in governmental repurchase agreements, commingled funds and pooled funds and mutual funds are valued at the net asset value per share multiplied by the number of shares held as of the measurement date.

[8] Other investments includes cash, forward contracts, derivative instruments, credit default swaps, interest rate swaps and mutual funds. Investments in interest rate swaps are valued utilizing a market approach that includes various valuation techniques and sources such as value generation models, broker quotes in active and non-active markets, benchmark yields and securities, reported trades, issuer trades and/or other applicable data. Forward contracts and derivative instruments are valued at their exchange listed price or broker quote in an active market. The mutual funds are valued at the net asset value per share multiplied by the number of shares held as of the measurement date and are traded on listed exchanges.

[9] Corporate fixed income is primarily comprised of corporate bonds and certain corporate asset-backed securities that are denominated in the U.S. dollar and are investment-grade securities. These investments are valued using dealer quotes.