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Costs incurred during the period related to the termination of a previously announced acquisition agreement.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to income that is exempt from income taxes under enacted tax laws.

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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This element represents the amount of interest expense accrued as of the date of the statement of financial position for an underpayment of income taxes computed by applying the applicable statutory rate of interest to the difference between a tax position recognized for financial reporting purposes and the amount previously taken or expected to be taken in a tax return of the entity.

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The net amount of all increases and decreases in unrecognized tax benefits for the period.

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Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 24, 2011	Mar. 26, 2011	Sep. 25, 2010	Jun. 26, 2010	Sep. 24, 2011 increment segment month subsidiaries Y	Sep. 25, 2010
Income Taxes
Income before income taxes	$ 24,541		$ (7,578)		$ 100,008	$ 38,901
Effective tax rate (as a percent)	22.90%		220.00%		11.60%	78.60%
Provision for income taxes	5,630		16,670		11,564	30,577
Termination fee			30,000			30,000
Change in indefinite reinvestment assertion			205,400	27,100
Tax exempt gain on the settlement of a life insurance policy					7,710
Income tax benefit associated with a tax loss incurred on the disposition of Phase I clinical business		11,111
Tax exempt gain from German tax audit	1,366
Remeasurement of deferred taxes for decline in statutory tax rate in United Kingdom	486				486
Income tax expense related to repatriated earnings	747
Decrease in unrecognized tax benefits					7,780
Unrecognized tax benefits	27,517				27,517
Decrease in unrecognized tax benefits that would impact effective tax rate favorably, if recognized	7,731
Unrecognized tax benefits that would impact effective tax rate favorably, if recognized	22,182				22,182
Maximum period within which it is reasonably possible that controversies with TCC and MRQ will conclude (in months)					12
Decrease in amount of accrued interest on unrecognized tax benefits	1,099
Amount of accrued interest on unrecognized tax benefits	$ 1,409				$ 1,409