Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 29, 2015	Dec. 31, 2014
Current assets:
Accounts receivable allowance for doubtful accounts	$ 791	$ 669
Stockholders' equity:
Preferred stock, shares authorized (in shares)	2,000,000us-gaap_PreferredStockSharesAuthorized	2,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued (in shares)	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Preferred stock, shares outstanding (in shares)	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common stock, par value per share (in usd per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	120,000,000us-gaap_CommonStockSharesAuthorized	120,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued (in shares)	79,183,000us-gaap_CommonStockSharesIssued	78,267,000us-gaap_CommonStockSharesIssued
Common stock, shares outstanding (in shares)	74,859,000us-gaap_CommonStockSharesOutstanding	74,009,000us-gaap_CommonStockSharesOutstanding
Treasury stock, shares (in shares)	4,324,000us-gaap_TreasuryStockShares	4,258,000us-gaap_TreasuryStockShares

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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