CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jul. 01, 2018
Cash flows from operating activities:
Net income	$ 27,682	$ 26,487
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	19,779	20,191
Provision for doubtful accounts	3,761	5,571
Stock-based compensation	5,260	5,983
Deferred income taxes	2,393	1,373
Non-cash lease expense	6,934	0
Other operating activities	(2,072)	102
Changes in operating assets and liabilities:
Accounts receivable	16,162	888
Income tax receivable	(6,347)	(3,641)
Other assets	(4,472)	(3,522)
Accounts payable and other accrued expenses	(16,542)	3,468
Accrued wages and benefits	(4,667)	(1,528)
Workers’ compensation claims reserve	(7,109)	(9,235)
Operating lease liabilities	(6,957)	0
Other liabilities	3,174	3,304
Net cash provided by operating activities	36,979	49,441
Cash flows from investing activities:
Capital expenditures	(11,064)	(6,468)
Payments to Acquire Businesses, Gross	0	(22,742)
Divestiture of business	0	8,800
Purchases of restricted investments	(11,315)	(10,730)
Maturities of restricted investments	19,685	13,044
Net cash used in investing activities	(2,694)	(18,096)
Cash flows from financing activities:
Payments for Repurchase of Common Stock	(9,077)	(19,065)
Net proceeds from employee stock purchase plans	700	757
Common stock repurchases for taxes upon vesting of restricted stock	(1,631)	(2,403)
Net change in revolving credit facility	(55,300)	21,300
Payments on debt	0	(22,856)
Other	(119)	0
Net cash used in financing activities	(65,427)	(22,267)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	560	(919)
Net change in cash, cash equivalents and restricted cash	(30,582)	8,159
Cash, cash equivalents and restricted cash, beginning of period	102,450	73,831
Cash, cash equivalents and restricted cash, end of period	71,868	81,990
Supplemental Cash Flow Information [Abstract]
Interest	1,199	1,892
Income taxes	7,277	5,696
Operating lease liabilities	8,798	0
Property and equipment purchased but not yet paid	1,227	726
Divestiture non-cash consideration	0	1,657
Right-of-use assets obtained in exchange for new operating lease liabilities	$ 7,711	$ 0