Convertible Senior Notes - Additional Information (Details) (USD $)	9 Months Ended			1 Months Ended	9 Months Ended
	Sep. 28, 2013	Sep. 29, 2012	Sep. 27, 2013	May 30, 2013 1.75% Convertible Senior Notes Due June 1, 2018 [Member]	Sep. 28, 2013 1.75% Convertible Senior Notes Due June 1, 2018 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Debt instrument issued				$ 150,000,000.0
Debt instrument interest percentage	1.75%			1.75%
Maturity date of debt instrument				Jun. 01, 2018
Frequency of payment of interest					payable semi-annually in arrears on June 1 and December 1 of each year
Net proceeds from issuance of debt	144,469,000	0			144,500,000
Initial conversion rate per $1,000 principal amount of Notes	79.4834
Principal amount of Notes, subject to anti-dilution adjustments	1,000
Initial conversion price	$ 12.58
Convertible threshold trading days	20 days
Convertible threshold consecutive trading days	30 days
Convertible threshold minimum percentage	130.00%
Convertible, threshold maximum percentage	98.00%
Purchase price as a percentage on principal amount of the notes upon the occurrence of a fundamental change	100.00%
Remaining contractual life of senior notes					5 years
Debt instrument discount to be amortized					42,700,000
Debt Issuance Cost					5,500,000
Deferred tax liability related to Notes					17,000,000
Additional effective rate of interest to be used on amortized carrying value	5.12%
Total estimated fair value of the notes	$ 173,600,000
Closing price of common stock			$ 11.40