Revenue from Contracts with Customers (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Dec. 29, 2018	Mar. 31, 2018	Dec. 30, 2017	Dec. 29, 2018	Dec. 30, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accrued Liabilities, Current	$ 126,228	$ 126,500		$ 126,228
Liabilities, Current	186,108	176,329		186,108
Deferred income taxes	7,001	7,577		7,001
Retained earnings	260,107	209,381		260,107
Stockholders' Equity Attributable to Parent	509,072	457,106		509,072
Revenues	233,700		$ 221,383	721,633	$ 628,706
Cost of Revenue	184,679		171,527	571,720	502,330
Gross Profit	49,021		49,856	149,913	126,376
Selling, General and Administrative Expense	30,833		26,045	90,081	78,503
Operating Income (Loss)	18,188		23,811	59,832	47,873
Income before income taxes	16,947		23,669	60,600	47,819
Income Tax Expense (Benefit)	(3,563)		(2,242)	(11,949)	(8,457)
Net income	13,384		21,427	48,651	39,362
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accrued Liabilities, Current	128,716			128,716
Liabilities, Current	188,596			188,596
Deferred income taxes	6,333			6,333
Retained earnings	258,287			258,287
Stockholders' Equity Attributable to Parent	507,252			507,252
Revenues	225,551			690,655
Cost of Revenue	177,032			542,993
Gross Profit	48,519			147,662
Selling, General and Administrative Expense	30,805			89,609
Operating Income (Loss)	17,714			58,053
Income before income taxes	16,473			58,821
Income Tax Expense (Benefit)	(3,451)			(11,536)
Net income	13,022			47,285
Accounting Standards Update 2014-09 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Operating Results	(502)			(2,251)
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income	(362)			(1,366)
Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income	5,900		$ 5,500	18,700	$ 15,600
Revenue from Contract with Customer [Member] | Accounting Standards Update 2014-09 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income	(8,149)			(30,978)
Cost of Sales [Member] | Accounting Standards Update 2014-09 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income	(7,647)			(28,727)
Selling, General and Administrative Expenses [Member] | Accounting Standards Update 2014-09 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income	(28)			(472)
Operating Income (Loss) [Member] | Accounting Standards Update 2014-09 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income	(474)			(1,779)
Other Expense [Member] | Accounting Standards Update 2014-09 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income	$ 112			413
Accrued Liabilities [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income		$ 600		2,488
Other Current Liabilities [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income				2,488
Deferred Tax Asset [Domain]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income				(668)
Retained earnings
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income				(1,820)
Stockholders' Equity, Total [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income				$ (1,820)