Goodwill And Related Intangible Assets (Schedule Of Acquired Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2011	Dec. 31, 2010
Gross Carrying Amount, Finite-lived	$ 77,021	$ 52,650
Total acquired intangible assets, gross carrying amount	124,185	88,053
Total acquired intangible assets, accumulated amortization	24,877	21,752
Accumulated Amortization	24,877	21,752
Customer Relationships [Member]
Gross Carrying Amount, Finite-lived	48,876	42,469
Accumulated Amortization	18,946	16,832
Estimated Life, Minimum	5
Estimated Life, Maximum	16
Non-competition Agreements [Member]
Gross Carrying Amount, Finite-lived	2,857	2,656
Accumulated Amortization	2,119	1,921
Estimated Life, Minimum	5
Estimated Life, Maximum	10
Backlog [Member]
Gross Carrying Amount, Finite-lived	1,200
Accumulated Amortization	200
Estimated Life, Minimum	1
Estimated Life, Maximum	2
Trademarks [Member]
Gross Carrying Amount, Indefinite-lived	47,164	35,403
Gross Carrying Amount, Finite-lived	1,971	1,968
Accumulated Amortization	843	760
Estimated Life, Minimum	2
Estimated Life, Maximum	15
Unpatented Technology [Member]
Gross Carrying Amount, Finite-lived	22,117	5,557
Accumulated Amortization	$ 2,769	$ 2,239
Estimated Life, Minimum	5
Estimated Life, Maximum	20