CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 24, 2017
Cash flows from operating activities
Net income	$ 70,484	$ 64,676
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	43,969	46,961
Stock-based compensation expense	9,969	10,927
Undistributed (gain)/loss of joint ventures	9	(31,464)
Long-term retirement benefit obligations	(19,769)	(21,897)
Other-net	351	2,748
Changes in operating assets and liabilities:
Accounts receivable-net	27,024	55,032
Other assets	6,226	(1,761)
Accounts payable, accrued payroll and other liabilities	(28,702)	12,473
Unexpired subscriptions	6,815	10,200
Net cash provided by operating activities	116,376	147,895
Cash flows from investing activities
Purchases of marketable securities	(386,842)	(398,246)
Maturities of marketable securities	346,601	454,022
Capital expenditures	(61,983)	(47,831)
Other-net	(1,585)	648
Net cash (used in)/provided by investing activities	(103,809)	8,593
Long-term obligations:
Repayment of debt and capital lease obligations	(414)	(414)
Dividends paid	(19,761)	(19,483)
Capital shares:
Proceeds from stock option exercises	40,650	4,142
Share-based compensation tax withholding	(9,048)	(3,984)
Net cash provided by/(used in) financing activities	11,427	(19,739)
Net increase in cash, cash equivalents and restricted cash	23,994	136,749
Effect of exchange rate changes on cash	(540)	294
Cash, cash equivalents and restricted cash at the beginning of the period	200,936	125,550
Cash, cash equivalents and restricted cash at the end of the period	$ 224,390	$ 262,593