CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 27, 2015	Mar. 28, 2014
Cash flows from operating activities:
Net income	$ 5,716us-gaap_NetIncomeLoss	$ 1,656us-gaap_NetIncomeLoss
Adjustments to reconcile net income to net cash from operating activities:
Depreciation and amortization	10,520us-gaap_DepreciationAndAmortization	5,161us-gaap_DepreciationAndAmortization
Provision for doubtful accounts	1,745us-gaap_ProvisionForDoubtfulAccounts	3,487us-gaap_ProvisionForDoubtfulAccounts
Stock-based compensation	3,389us-gaap_ShareBasedCompensation	2,876us-gaap_ShareBasedCompensation
Deferred income taxes	(299)us-gaap_DeferredIncomeTaxExpenseBenefit	(1,433)us-gaap_DeferredIncomeTaxExpenseBenefit
Other operating activities	(316)us-gaap_OtherNoncashIncomeExpense	(435)us-gaap_OtherNoncashIncomeExpense
Changes in operating assets and liabilities:
Accounts receivable	67,411	9,949
Income taxes	943	3,567
Other assets	4,496	(331)
Accounts payable and other accrued expenses	4,369	(3,307)
Accrued wages and benefits	(3,999)	1,380
Workers’ compensation claims reserve	159	261
Other liabilities	1,626	664
Net cash provided by operating activities	95,760	23,495
Cash flows from investing activities:
Capital expenditures	(3,458)	(2,091)
Purchases of marketable securities	0	(25,057)
Sales and maturities of marketable securities	1,500	9,450
Change in restricted cash and cash equivalents	(8,215)	(1,491)
Maturities of restricted investments	4,288	4,215
Net cash used in investing activities	(5,885)	(14,974)
Cash flows from financing activities:
Net proceeds from stock option exercises and employee stock purchase plans	411	602
Common stock repurchases for taxes upon vesting of restricted stock	(3,026)	(2,474)
Net change in revolving credit facility	(88,000)	0
Payments on debt and other liabilities	(566)	(567)
Other	865	973
Net cash used in financing activities	(90,316)	(1,466)
Effect of exchange rate changes on cash and cash equivalents	(1,446)	(240)
Net change in cash and cash equivalents	(1,887)	6,815
CASH AND CASH EQUIVALENTS, beginning of period	19,666	122,003
CASH AND CASH EQUIVALENTS, end of period	$ 17,779	$ 128,818

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.