Finance Receivables - Allowance For Credit Losses And Finance Receivables By Portfolio, Individually And Collectively Evaluated For Impairment (Details) - USD ($) $ in Thousands	Sep. 27, 2020	Jun. 28, 2020	Dec. 31, 2019	Sep. 29, 2019	Jun. 30, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Losses
Individually evaluated for impairment			$ 2,100	$ 0
Collectively evaluated for impairment			196,481	198,576
Total allowance for credit losses	$ 408,702	$ 411,015	198,581	198,576	$ 194,996	$ 189,885
Individually evaluated for impairment			4,601	0
Collectively evaluated for impairment			7,568,346	7,714,156
Total	7,252,194		7,572,947	7,714,156
Retail
Financing Receivable, Allowance for Credit Losses
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			188,501	191,626
Total allowance for credit losses	390,076	389,758	188,501	191,626	186,722	182,098
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			6,416,428	6,642,809
Total	6,585,298		6,416,428	6,642,809
Wholesale
Financing Receivable, Allowance for Credit Losses
Individually evaluated for impairment			2,100	0
Collectively evaluated for impairment			7,980	6,950
Total allowance for credit losses	18,626	$ 21,257	10,080	6,950	$ 8,274	$ 7,787
Individually evaluated for impairment			4,601	0
Collectively evaluated for impairment			1,151,918	1,071,347
Total	$ 666,896		$ 1,156,519	$ 1,071,347