CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net earnings	$ 100,306,000	$ 122,319,000	$ 178,391,000
Adjustments to reconcile net earnings to net cash flows from operations:
Depreciation and amortization	82,827,000	84,957,000	82,417,000
Noncash loss on trading securities	(62,000)	237,000	586,000
Contribution to defined benefit pension plan	(1,537,000)	(40,245,000)	(1,488,000)
Impairment of property, plant and equipment	5,000,000	0	1,099,000
Impairment of goodwill & intangible assets	15,780,000	0	0
Loss on divestiture of grinding media business	6,084,000	0	0
Stock-based compensation	10,392,000	10,706,000	9,931,000
Change in fair value of contingent consideration	0	0	(3,242,000)
Defined benefit pension plan expense (benefit)	(2,251,000)	648,000	1,870,000
(Gain) loss on sale of property, plant and equipment	(225,000)	(3,924,000)	631,000
Equity in earnings in nonconsolidated subsidiaries	0	0	0
Deferred income taxes	(1,659,000)	39,755,000	(23,685,000)
Changes in assets and liabilities (net of acquisitions):
Receivables	12,571,000	(49,112,000)	24,622,000
Inventories	(13,774,000)	(57,442,000)	(11,461,000)
Prepaid expenses	(11,048,000)	(6,214,000)	(1,925,000)
Contract asset - costs and profits in excess of billings	(32,932,000)	176,000	3,063,000
Accounts payable	(1,486,000)	39,405,000	104,000
Accrued expenses	49,000	(1,998,000)	(12,207,000)
Other noncurrent liabilities	(10,888,000)	(7,228,000)	(23,880,000)
Income taxes payable (refundable)	(4,139,000)	1,108,000	7,994,000
Net cash flows from operating activities	153,008,000	133,148,000	232,820,000
Cash flows from investing activities:
Purchase of property, plant and equipment	(71,985,000)	(55,266,000)	(57,920,000)
Proceeds from sale of assets	63,103,000	8,185,000	5,126,000
Acquisitions, net of cash acquired	(143,020,000)	(5,362,000)	0
Proceeds from settlement of net investment hedge	(1,621,000)	5,123,000	0
Other, net	(1,922,000)	(2,295,000)	(255,000)
Net cash flows used in investing activities	(155,445,000)	(49,615,000)	(53,049,000)
Cash flows from financing activities:
Borrowings (Payments) under short-term agreements	10,543,000	(585,000)	(200,000)
Proceeds from long-term borrowings	251,655,000	0	0
Principal payments on long-term borrowings	(262,191,000)	(887,000)	(2,006,000)
Payments for Derivative Instrument, Financing Activities	2,467,000	0	0
Payments of Debt Issuance Costs	(2,322,000)	0	0
Dividends paid	(33,726,000)	(33,862,000)	(34,053,000)
Dividends to noncontrolling interest	(7,055,000)	(5,674,000)	(2,938,000)
Purchase of noncontrolling interest	(5,510,000)	0	(11,009,000)
Proceeds from exercises under stock plans	7,357,000	35,159,000	11,153,000
Purchase of treasury shares	(114,805,000)	0	(53,800,000)
Purchase of common treasury shares—stock plan exercises	(3,589,000)	(26,161,000)	(2,305,000)
Net cash flows used in financing activities	(162,110,000)	(32,010,000)	(95,158,000)
Effect of exchange rate changes on cash and cash equivalents	(15,048,000)	27,682,000	(20,087,000)
Net change in cash and cash equivalents	(179,595,000)	79,205,000	64,526,000
Cash, cash equivalents, and restricted cash—end of year			399,948,000
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 313,210,000	$ 492,805,000	$ 413,600,000