A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of the cumulative effect on retained earnings net of related income tax effect.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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Business Overview and Summary of Significant Accounting Policies (Details) - USD ($)		12 Months Ended
	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax		$ 8,804,000	$ 6,241,000
Concentration Risks, Types, No Concentration Percentage [Abstract]
Allowance for Doubtful Accounts Receivable, Current		0	0
Provision for Doubtful Accounts		$ 0	$ 0	$ 0
Building and improvements \| Minimum
Estimated useful life		10 years
Building and improvements \| Maximum
Estimated useful life		50 years
Laboratory and other equipment \| Minimum
Estimated useful life		3 years
Laboratory and other equipment \| Maximum
Estimated useful life		10 years
Furniture and Fixtures [Member] \| Maximum
Estimated useful life		5 years
Accounting Standards Update 2014-09 [Member]
Cumulative Effect on Retained Earnings, Tax	$ 140,000,000
Gross Sales Revenue \| Customer concentration risk
Concentration risk, percentage		99.00%	99.00%
Equity Securities [Member] \| Unrestricted
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax		$ 6,594,000	$ 5,551,000