GUARANTOR/NON-GUARANTOR FINANCIAL INFORMATION - Condensed Consolidated Statements of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Cash flows from operating activities:
Net earnings	$ 42,346	$ 34,680	$ 79,801	$ 75,160
Adjustments to reconcile net earnings to net cash flows from operations:
Depreciation and amortization			40,583	41,657
Noncash loss on trading securities			28	229
Impairment of property, plant and equipment			0	2,791
Loss on divestiture of grinding media business	0	6,084	0	6,084
Stock-based compensation			6,370	5,374
Defined benefit pension plan benefit			(259)	(1,159)
Contribution to defined benefit pension plan			(13,682)	(731)
Gain on sale of property, plant and equipment			(278)	(287)
Equity in earnings in nonconsolidated subsidiaries	0	0	0	0
Deferred income taxes	(3,952)	(2,319)	5,710	2,500
Changes in assets and liabilities:
Net working capital			7,677	(73,192)
Other noncurrent liabilities			(5,582)	(480)
Income taxes payable (refundable)			(6,931)	(4,288)
Net cash flows from operating activities			113,437	53,658
Cash flows from investing activities:
Purchase of property, plant and equipment			(49,310)	(31,816)
Proceeds from sale of assets			466	64,393
Acquisitions, net of cash acquired			(81,841)	(9,300)
Settlement of net investment hedge			11,184	(1,621)
Other, net			3,893	2,404
Net cash flows from investing activities			(115,608)	24,060
Cash flows from financing activities:
Proceeds from short-term agreements			9,886	130
Proceeds from long-term borrowings			31,000	237,641
Principal payments on long-term borrowings			(10,386)	(495)
Settlement of financial derivatives			0	(2,467)
Debt issuance costs			0	(2,322)
Principal payments on long-term intercompany note			0
Dividends paid			(16,425)	(17,003)
Dividends to noncontrolling interest			(4,459)	(4,852)
Intercompany dividends			0	0
Purchase of noncontrolling interest			(27,845)	(5,510)
Intercompany capital contribution			0	0
Purchase of treasury shares			(38,350)	(43,999)
Proceeds from exercises under stock plans			1,744	5,711
Purchase of common treasury shares - stock plan exercises			(827)	(1,769)
Net cash flows from financing activities			(55,662)	165,065
Effect of exchange rate changes on cash and cash equivalents			1,567	(13,000)
Net change in cash and cash equivalents			(56,266)	229,783
Cash, cash equivalents, and restricted cash—beginning of year			313,210	492,805
Cash, cash equivalents, and restricted cash—end of year	256,944	722,588	256,944	722,588
Eliminations
Cash flows from operating activities:
Net earnings	(21,286)	(52,879)	(51,760)	(78,620)
Adjustments to reconcile net earnings to net cash flows from operations:
Depreciation and amortization			0	0
Noncash loss on trading securities			0	0
Impairment of property, plant and equipment				0
Loss on divestiture of grinding media business		0		0
Stock-based compensation			0	0
Defined benefit pension plan benefit			0	0
Contribution to defined benefit pension plan			0	0
Gain on sale of property, plant and equipment			0	0
Equity in earnings in nonconsolidated subsidiaries	20,785	52,460	51,578	79,776
Deferred income taxes			0	0
Changes in assets and liabilities:
Net working capital			175	(1,244)
Other noncurrent liabilities			0	0
Income taxes payable (refundable)			(909)	0
Net cash flows from operating activities			(916)	(88)
Cash flows from investing activities:
Purchase of property, plant and equipment			0	0
Proceeds from sale of assets			0	0
Acquisitions, net of cash acquired			0	0
Settlement of net investment hedge			0	0
Other, net			916	88
Net cash flows from investing activities			916	88
Cash flows from financing activities:
Proceeds from short-term agreements			0	0
Proceeds from long-term borrowings			0	0
Principal payments on long-term borrowings			0	0
Settlement of financial derivatives				0
Debt issuance costs				0
Principal payments on long-term intercompany note			0
Dividends paid			0	0
Dividends to noncontrolling interest			0	0
Intercompany dividends			0	0
Purchase of noncontrolling interest			0	0
Intercompany capital contribution			0	0
Purchase of treasury shares			0	0
Proceeds from exercises under stock plans			0	0
Purchase of common treasury shares - stock plan exercises			0	0
Net cash flows from financing activities			0	0
Effect of exchange rate changes on cash and cash equivalents			0	0
Net change in cash and cash equivalents			0	0
Cash, cash equivalents, and restricted cash—beginning of year			0	0
Cash, cash equivalents, and restricted cash—end of year	0	0	0	0
Parent
Cash flows from operating activities:
Net earnings	41,397	32,960	77,878	72,241
Adjustments to reconcile net earnings to net cash flows from operations:
Depreciation and amortization			13,094	12,871
Noncash loss on trading securities			0	0
Impairment of property, plant and equipment				0
Loss on divestiture of grinding media business		2,518		2,518
Stock-based compensation			6,370	5,374
Defined benefit pension plan benefit			0	0
Contribution to defined benefit pension plan			0	0
Gain on sale of property, plant and equipment			132	10
Equity in earnings in nonconsolidated subsidiaries	(17,903)	(21,291)	(44,752)	(45,878)
Deferred income taxes			1,317	3,343
Changes in assets and liabilities:
Net working capital			15,058	(15,781)
Other noncurrent liabilities			3,596	640
Income taxes payable (refundable)			(265)	(11,054)
Net cash flows from operating activities			72,428	24,284
Cash flows from investing activities:
Purchase of property, plant and equipment			(26,526)	(10,051)
Proceeds from sale of assets			6	5
Acquisitions, net of cash acquired			0	0
Settlement of net investment hedge			11,184	(1,621)
Other, net			(68,443)	6,335
Net cash flows from investing activities			(83,779)	(5,332)
Cash flows from financing activities:
Proceeds from short-term agreements			0	0
Proceeds from long-term borrowings			31,000	237,641
Principal payments on long-term borrowings			(10,000)	0
Settlement of financial derivatives				(2,467)
Debt issuance costs				(2,322)
Principal payments on long-term intercompany note			0
Dividends paid			(16,425)	(17,003)
Dividends to noncontrolling interest			0	0
Intercompany dividends			63,650	75,325
Purchase of noncontrolling interest			(22,805)	0
Intercompany capital contribution			(13,284)	(3,492)
Purchase of treasury shares			(38,350)	(43,999)
Proceeds from exercises under stock plans			1,744	5,711
Purchase of common treasury shares - stock plan exercises			(827)	(1,769)
Net cash flows from financing activities			(5,297)	247,625
Effect of exchange rate changes on cash and cash equivalents			0	0
Net change in cash and cash equivalents			(16,648)	266,577
Cash, cash equivalents, and restricted cash—beginning of year			104,256	83,329
Cash, cash equivalents, and restricted cash—end of year	87,608	349,906	87,608	349,906
Guarantors
Cash flows from operating activities:
Net earnings	10,459	44,967	34,020	55,956
Adjustments to reconcile net earnings to net cash flows from operations:
Depreciation and amortization			6,888	7,063
Noncash loss on trading securities			0	0
Impairment of property, plant and equipment				0
Loss on divestiture of grinding media business		0		0
Stock-based compensation			0	0
Defined benefit pension plan benefit			0	0
Contribution to defined benefit pension plan			0	0
Gain on sale of property, plant and equipment			44	(7)
Equity in earnings in nonconsolidated subsidiaries	(2,882)	(31,169)	(6,826)	(33,898)
Deferred income taxes			0	1,791
Changes in assets and liabilities:
Net working capital			(29,557)	(43,990)
Other noncurrent liabilities			(5,461)	0
Income taxes payable (refundable)			(1,819)	(843)
Net cash flows from operating activities			(2,711)	(13,928)
Cash flows from investing activities:
Purchase of property, plant and equipment			(3,213)	(6,770)
Proceeds from sale of assets			38	209
Acquisitions, net of cash acquired			(63,141)	0
Settlement of net investment hedge			0	0
Other, net			64,103	13,752
Net cash flows from investing activities			(2,213)	7,191
Cash flows from financing activities:
Proceeds from short-term agreements			0	0
Proceeds from long-term borrowings			0	0
Principal payments on long-term borrowings			0	0
Settlement of financial derivatives				0
Debt issuance costs				0
Principal payments on long-term intercompany note			(42,574)
Dividends paid			0	0
Dividends to noncontrolling interest			0	0
Intercompany dividends			47,541	11,296
Purchase of noncontrolling interest			0	0
Intercompany capital contribution			0	3,492
Purchase of treasury shares			0	0
Proceeds from exercises under stock plans			0	0
Purchase of common treasury shares - stock plan exercises			0	0
Net cash flows from financing activities			4,967	14,788
Effect of exchange rate changes on cash and cash equivalents			54	(657)
Net change in cash and cash equivalents			97	7,394
Cash, cash equivalents, and restricted cash—beginning of year			5,518	5,304
Cash, cash equivalents, and restricted cash—end of year	5,615	12,698	5,615	12,698
Non- Guarantors
Cash flows from operating activities:
Net earnings	11,776	9,632	19,663	25,583
Adjustments to reconcile net earnings to net cash flows from operations:
Depreciation and amortization			20,601	21,723
Noncash loss on trading securities			28	229
Impairment of property, plant and equipment				2,791
Loss on divestiture of grinding media business		3,566		3,566
Stock-based compensation			0	0
Defined benefit pension plan benefit			(259)	(1,159)
Contribution to defined benefit pension plan			(13,682)	(731)
Gain on sale of property, plant and equipment			(454)	(290)
Equity in earnings in nonconsolidated subsidiaries	0	0	0	0
Deferred income taxes			4,393	(2,634)
Changes in assets and liabilities:
Net working capital			22,001	(12,177)
Other noncurrent liabilities			(3,717)	(1,120)
Income taxes payable (refundable)			(3,938)	7,609
Net cash flows from operating activities			44,636	43,390
Cash flows from investing activities:
Purchase of property, plant and equipment			(19,571)	(14,995)
Proceeds from sale of assets			422	64,179
Acquisitions, net of cash acquired			(18,700)	(9,300)
Settlement of net investment hedge			0	0
Other, net			7,317	(17,771)
Net cash flows from investing activities			(30,532)	22,113
Cash flows from financing activities:
Proceeds from short-term agreements			9,886	130
Proceeds from long-term borrowings			0	0
Principal payments on long-term borrowings			(386)	(495)
Settlement of financial derivatives				0
Debt issuance costs				0
Principal payments on long-term intercompany note			42,574
Dividends paid			0	0
Dividends to noncontrolling interest			(4,459)	(4,852)
Intercompany dividends			(111,191)	(86,621)
Purchase of noncontrolling interest			(5,040)	(5,510)
Intercompany capital contribution			13,284	0
Purchase of treasury shares			0	0
Proceeds from exercises under stock plans			0	0
Purchase of common treasury shares - stock plan exercises			0	0
Net cash flows from financing activities			(55,332)	(97,348)
Effect of exchange rate changes on cash and cash equivalents			1,513	(12,343)
Net change in cash and cash equivalents			(39,715)	(44,188)
Cash, cash equivalents, and restricted cash—beginning of year			203,436	404,172
Cash, cash equivalents, and restricted cash—end of year	$ 163,721	$ 359,984	$ 163,721	$ 359,984