Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Carrying value of intangible assets
Goodwill, gross carrying amount	$ 348,032	$ 322,556
Goodwill, accumulated amortization	0	0
Goodwill, net carrying amount	348,032	322,556	273,126
Definite-lived Intangible assets subject to amortization:
Finite-lived intangible assets, gross carrying amount	164,469	146,994
Finite-lived intangible assets, Accumulated amortization	(57,782)	(43,341)
Finite-lived intangible assets, net carrying amount	106,687	103,653
Intangible assets, gross carrying amount	209,465	187,161
Intangible assets, net carrying amount	151,683	143,820
Customer relationships [Member]
Definite-lived Intangible assets subject to amortization:
Finite-lived intangible assets, gross carrying amount	121,472	107,503
Finite-lived intangible assets, Accumulated amortization	(27,088)	(19,711)
Finite-lived intangible assets, net carrying amount	94,384	87,792
Developed technologies [Member]
Definite-lived Intangible assets subject to amortization:
Finite-lived intangible assets, gross carrying amount	39,320	36,508
Finite-lived intangible assets, Accumulated amortization	(27,364)	(20,647)
Finite-lived intangible assets, net carrying amount	11,956	15,861
Backlog [Member]
Definite-lived Intangible assets subject to amortization:
Finite-lived intangible assets, gross carrying amount	3,286	2,983
Finite-lived intangible assets, Accumulated amortization	(3,286)	(2,983)
Finite-lived intangible assets, net carrying amount	0	0
Trademarks [Member]
Definite-lived Intangible assets subject to amortization:
Finite-lived intangible assets, gross carrying amount	391	0
Finite-lived intangible assets, Accumulated amortization	(44)	0
Finite-lived intangible assets, net carrying amount	347	0
Intangible Assets Not Subject To Amortization [Member]
Definite-lived Intangible assets subject to amortization:
Indefinite-lived intangible assets, Carrying amount	44,996	40,167
Indefinite lived intangible assets, accumulated amortization	$ 0	$ 0

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- Definition

Indefinite lived intangible assets, excluding goodwill, accumulated amortization.

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Intangible assets gross excluding goodwill.

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The accumulated amount of amortization of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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Sum of the gross carrying amounts before accumulated amortization as of the balance sheet date of all intangible assets having statutory or estimated useful lives. The aggregate gross carrying amount (including any previously recognized impairment charges) of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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The aggregate sum of gross carrying value of a major finite-lived intangible asset class, less accumulated amortization and any impairment charges. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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Gross amount, as of the balance sheet date, of the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable), in excess of the fair value of net assets acquired in one or more business combination transactions.

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The accumulated impairment losses related to goodwill as of the balance sheet date.

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Carrying amount of intangible assets, excluding goodwill, which have a projected indefinite period of benefit (hence are not amortized), allocated to the reportable segment. These assets, acquired either individually or as part of a group of assets, in either an asset acquisition or business combination, are assessed at least annually for impairment. Examples may include trade secrets, contractual rights, trade names, and licensing agreements.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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