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Segment Information (Concentration Risk by Customer) (Details) - Sales revenue, net [Member] - Customer concentration risk [Member]	12 Months Ended
	Dec. 29, 2017	Dec. 30, 2016	Jan. 01, 2016
Diplomat Specialty Pharmacy [Member]
Concentration Risk [Line Items]
Concentration risk	18.00%	33.00%	83.00%
Caremark L.L.C. [Member]
Concentration Risk [Line Items]
Concentration risk	16.00%	9.00%	0.00%
Ipsen [Member]
Concentration Risk [Line Items]
Concentration risk	15.00%	17.00%	0.00%
Accredo Health, Incorporated [Member]
Concentration Risk [Line Items]
Concentration risk	11.00%	9.00%	0.00%
Affiliates of McKesson Corporation [Member]
Concentration Risk [Line Items]
Concentration risk	11.00%	7.00%	0.00%

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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-Section 50
-Paragraph 20
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
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-Paragraph 21
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