Supplemental Stockholders' Equity Information - Changes in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 29, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, beginning of period	$ 1,173,863	$ 1,042,641
Other comprehensive (loss)/income before reclassifications, before tax	461
Amounts reclassified from accumulated other comprehensive loss, before tax	6,397
Income tax (benefit)/expense	1,915	1,399
Other comprehensive income, net of tax	4,943	3,922
Balance, end of period	1,193,574	1,059,814
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, beginning of period	3,438
Other comprehensive (loss)/income before reclassifications, before tax	(254)
Amounts reclassified from accumulated other comprehensive loss, before tax	0
Income tax (benefit)/expense	(68)
Other comprehensive income, net of tax	(186)
Balance, end of period	3,252
Funded Status of Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, beginning of period	(498,986)
Other comprehensive (loss)/income before reclassifications, before tax	0
Amounts reclassified from accumulated other comprehensive loss, before tax	6,397
Income tax (benefit)/expense	1,794
Other comprehensive income, net of tax	4,603
Balance, end of period	(494,383)
Net unrealized Loss on available-for-sale Securities
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, beginning of period	572
Other comprehensive (loss)/income before reclassifications, before tax	715
Amounts reclassified from accumulated other comprehensive loss, before tax	0
Income tax (benefit)/expense	189
Other comprehensive income, net of tax	526
Balance, end of period	1,098
Accumulated Other Comprehensive Loss, Net of Income Taxes
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, beginning of period	(494,976)	(517,724)
Other comprehensive income, net of tax	4,943	3,922
Balance, end of period	$ (490,033)	$ (513,802)