CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended			19 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013	Dec. 26, 2015
Cash flows from operating activities:
Net earnings	$ 45,333	$ 189,318	$ 280,460
Adjustments to reconcile net earnings to net cash flows from operations:
Depreciation and amortization	91,144	89,328	77,436
Noncash loss on trading securities	4,555	3,795	0
Non-cash after-tax loss on deconsolidation	0	0	12,011
Impairment of assets - restructuring activities	19,836		12,161
Impairment of goodwill & intangible assets	41,970	0	0
Non-cash debt refinancing costs	0	(2,478)	0
Stock-based compensation	7,244	6,730	6,513
Change in fair value of contingent consideration	0	(4,300)	0
Defined benefit pension plan expense (benefit)	(610)	2,638	6,569
Contribution to defined benefit pension plan	(16,500)	(18,173)	(17,619)
(Gain) loss on sale of property, plant and equipment	2,327	392	(4,318)
Equity in earnings in nonconsolidated subsidiaries	247	(29)	(835)
Deferred income taxes	4,858	5,251	(10,141)
Changes in assets and liabilities (net of acquisitions):
Receivables	50,267	907	(12,708)
Inventories	3,296	21,458	13,431
Prepaid expenses	10,844	(13,594)	4,115
Accounts payable	(6,805)	(34,321)	12,448
Accrued expenses	8,918	(34,778)	21,698
Other noncurrent liabilities	(1,764)	1,755	(1,474)
Income taxes payable (refundable)	7,107	(39,803)	(3,305)
Net cash flows from operating activities	272,267	174,096	396,442
Cash flows from investing activities:
Purchase of property, plant and equipment	(45,468)	(73,023)	(106,753)
Proceeds from sale of assets	3,249	2,489	37,582
Acquisitions, net of cash acquired	(12,778)	(185,710)	(63,152)
Other, net	6,826	(619)	602
Net cash flows from investing activities	(48,171)	(256,863)	(131,721)
Cash flows from financing activities:
Net borrowings under short-term agreements	(12,853)	(4,472)	5,510
Proceeds from long-term borrowings	68,000	652,211	274
Principal payments on long-term borrowings	(69,098)	(357,858)	(591)
vmi_PaymentsOnDeconsolidationOfSubsidiary	0	0	(11,615)
Settlement of financial derivatives	0	4,981	0
Dividends paid	(35,357)	(32,443)	(25,414)
Dividends to noncontrolling interest	(2,634)	(2,919)	(1,767)
Payments to Acquire Additional Interest in Subsidiaries	0	0	(9,324)
Debt issuance costs	0	(7,644)	0
Purchase of treasury shares	(168,983)	(395,045)	0	$ (564,000)
Proceeds from exercises under stock plans	13,075	14,572	16,348
Excess tax benefits from stock option exercises	1,699	4,264	5,306
Purchase of common treasury shares—stock plan exercises	(13,854)	(15,403)	(16,107)
Net cash flows from financing activities	(220,005)	(139,756)	(37,380)
Effect of exchange rate changes on cash and cash equivalents	(26,596)	(19,604)	(27,764)
Net change in cash and cash equivalents	(22,505)	(242,127)	199,577
Cash and cash equivalents—beginning of year	371,579	613,706	414,129
Cash and cash equivalents—end of period	$ 349,074	$ 371,579	$ 613,706	$ 349,074