Other Comprehensive Income Changes in accumulated other comprehensive income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Apr. 01, 2017
Accumulated Other Comprehensive Income/(Loss) [Line Items]
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, Tax	$ (1,300)
Other than Temporary Impairment Loss, Investments, Portion in Other Comprehensive Loss, Tax, Attributable to Parent, Held-to-maturity Securities	(44,900)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax	4,300
Currency Translation Adjustment	21,802	$ 10,835
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(266,419)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	20,627
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	8,874	$ 2,527
Reclassification from accumulated other comprehensive income, current period, net of tax	(12)
Other Comprehensive Income (Loss), before Reclassifications, before Tax	19,483
Accumulated Other Comprehensive Income (Loss), Net of Tax	(246,936)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax	100
Stranded Tax Effects Reclassified from OCI to Retained Earnings	1,132
Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income/(Loss) [Line Items]
Currency Translation Adjustment	21,802
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(69,721)
Reclassification from accumulated other comprehensive income, current period, net of tax	0
Other Comprehensive Income (Loss), before Reclassifications, before Tax	21,802
Accumulated Other Comprehensive Income (Loss), Net of Tax	(47,919)
Stranded Tax Effects Reclassified from OCI to Retained Earnings	0
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(203,063)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	(9,361)
Reclassification from accumulated other comprehensive income, current period, net of tax	0
Other Comprehensive Income (Loss), before Reclassifications, before Tax	(8,874)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(211,937)
Stranded Tax Effects Reclassified from OCI to Retained Earnings	(500)
Interest Rate Swap [Member] | Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax	6,365
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	8,186
Reclassification from accumulated other comprehensive income, current period, net of tax	(12)
Other Comprehensive Income (Loss), before Reclassifications, before Tax	6,555
Accumulated Other Comprehensive Income (Loss), Net of Tax	12,920
Stranded Tax Effects Reclassified from OCI to Retained Earnings	$ 1,600