Financial Instruments and Fair Value Measurements (Schedules of Concentration of Risk) (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 28, 2018	Sep. 29, 2017	Sep. 28, 2018	Sep. 29, 2017	Dec. 29, 2017
Distributor Concentration Risk | Net Sales Attributable to Distributors | CuraScript, Inc
Concentration Risk
Concentration Risk, Percentage	44.90%	55.20%	46.10%	55.70%
Distributor Concentration Risk | Accounts Receivable Attributable to Distributors | CuraScript, Inc
Concentration Risk
Concentration Risk, Percentage			30.80%		33.80%
Product Concentration Risk | Net Sales Attributable to Products | Acthar
Concentration Risk
Concentration Risk, Percentage	45.30%	51.40%	44.80%	51.10%
Product Concentration Risk | Net Sales Attributable to Products | Inomax
Concentration Risk
Concentration Risk, Percentage	20.80%	20.90%	21.90%	21.60%
Product Concentration Risk | Net Sales Attributable to Products | Ofirmev
Concentration Risk
Concentration Risk, Percentage	13.60%	12.60%	13.80%	12.80%