Revenues - Activities and Ending Reserve Balances for Significant Categories of Discounts and Allowances (Details) $ in Thousands	3 Months Ended
Mar. 30, 2018 USD ($)
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance	$ 9,493
Provision related to sales made in:
Current period	25,297
Prior periods	(132)
Payments and customer credits issued	(20,153)
Balance	14,505
Chargebacks and Discounts for Prompt Payment
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance	1,928
Provision related to sales made in:
Current period	14,475
Prior periods	(331)
Payments and customer credits issued	(13,556)
Balance	2,516
Other Customer Credits/Fees and Co-pay Assistance
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance	1,795
Provision related to sales made in:
Current period	4,197
Prior periods	0
Payments and customer credits issued	(3,294)
Balance	2,698
Rebates
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance	5,770
Provision related to sales made in:
Current period	6,625
Prior periods	199
Payments and customer credits issued	(3,303)
Balance	9,291
Returns
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance	0
Provision related to sales made in:
Current period	0
Prior periods	0
Payments and customer credits issued	0
Balance	$ 0

Valuation Allowances And Reserves, Additions For Sales In Current Period

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- Definition

Valuation Allowances And Reserves, Additions For Sales In Prior Period

+ References

No definition available.

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- Definition

Valuation Allowances And Reserves, Additions To Provision [Abstract]

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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- Definition

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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