Stockholders' Equity (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Dec. 28, 2019	Dec. 29, 2018
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, common stock, shares			9,098,320				9,098,320
Ending balance, common stock, shares	9,141,191						9,141,191
Beginning balance	$ 573,004	$ 550,337	$ 529,588	$ 494,748	$ 475,687	$ 457,106	$ 529,588	$ 457,106
Net income	20,898	20,885	21,282	13,384	15,576	19,691	63,065	48,651
Issuance of common stock under stock incentive plans	537	941	(1,252)	59	1,995	(2,168)
Stock-based compensation	820	818	630	821	1,516	599
Other comprehensive income, net	1	23	89	60	(26)	5
Ending balance	$ 595,260	$ 573,004	$ 550,337	$ 509,072	$ 494,748	$ 475,687	$ 595,260	$ 509,072
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, common stock, shares	9,127,466	9,111,624	9,098,320	9,097,359	9,061,306	9,044,858	9,098,320	9,044,858
Issuance of common stock under stock incentive plans, shares	13,725	15,842	13,304	961	36,053	16,448
Ending balance, common stock, shares	9,141,191	9,127,466	9,111,624	9,098,320	9,097,359	9,061,306	9,141,191	9,098,320
Beginning balance	$ 91	$ 91	$ 91	$ 91	$ 91	$ 90	$ 91	$ 90
Net income	0	0	0	0	0	0
Issuance of common stock under stock incentive plans	0	0	0	0	0	1
Stock-based compensation	0	0	0	0	0	0
Other comprehensive income, net	0	0	0	0	0	0
Ending balance	91	91	91	91	91	91	91	91
Additional paid-in capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	250,584	248,825	249,447	248,138	244,627	246,197	249,447	246,197
Net income	0	0	0	0	0	0
Issuance of common stock under stock incentive plans	537	941	(1,252)	59	1,995	(2,169)
Stock-based compensation	820	818	630	821	1,516	599
Other comprehensive income, net	0	0	0	0	0	0
Ending balance	251,941	250,584	248,825	249,018	248,138	244,627	251,941	249,018
Retained earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	322,245	301,360	280,078	246,723	231,147	209,381	280,078	209,381
Net income	20,898	20,885	21,282	13,384	15,576	19,691
Issuance of common stock under stock incentive plans	0	0	0	0	0	0
Stock-based compensation	0	0	0	0	0	0
Other comprehensive income, net	0	0	0	0	0	0
Ending balance	343,143	322,245	301,360	260,107	246,723	231,147	343,143	260,107
Accumulated other comprehensive income (loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	84	61	(28)	(204)	(178)	1,438	(28)	1,438
Net income	0	0	0	0	0	0
Issuance of common stock under stock incentive plans	0	0	0	0	0	0
Stock-based compensation	0	0	0	0	0	0
Other comprehensive income, net	1	23	89	60	(26)	5
Ending balance	$ 85	$ 84	$ 61	$ (144)	$ (204)	(178)	$ 85	$ (144)
ASU 2016-01, net
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets						0
ASU 2016-01, net | Common Stock
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets						0
ASU 2016-01, net | Additional paid-in capital
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets						0
ASU 2016-01, net | Retained earnings
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets						1,621
ASU 2016-01, net | Accumulated other comprehensive income (loss)
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets						(1,621)
ASC 606, net
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets						454
ASC 606, net | Common Stock
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets						0
ASC 606, net | Additional paid-in capital
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets						0
ASC 606, net | Retained earnings
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets						454
ASC 606, net | Accumulated other comprehensive income (loss)
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets						$ 0