Update to Significant Accounting Policies - Schedule rollforward of the allowance for credit losses for accounts receivable, notes receivable and other assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 29, 2020	Mar. 31, 2019	Dec. 30, 2019	Dec. 29, 2019
Credit Losses
Retained earnings	$ 202,287			$ 205,697
Income tax receivable	4,101			$ 4,024
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Current period provision for expected credit losses	768	$ (50)
Accounts Receivable
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	7,341
Balance at beginning of period, adjusted			$ 8,253
Current period provision for expected credit losses	625
Write-offs charged against the allowance	(380)
Balance at end of period	8,498
Notes Receivable
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	3,572
Balance at beginning of period, adjusted			4,035
Recoveries collected	(22)
Balance at end of period	4,013
Other Assets
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	910
Balance at beginning of period, adjusted			910
Current period provision for expected credit losses	144
Balance at end of period	1,054
ASU 2016-13 | Total Adjustments
Credit Losses
Retained earnings			1,100
Income tax receivable			$ 300
ASU 2016-13 | Total Adjustments | Accounts Receivable
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	911
ASU 2016-13 | Total Adjustments | Notes Receivable
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 463