Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Dec. 27, 2014	Dec. 28, 2013	Dec. 27, 2014	Dec. 28, 2013
Numerator For Earnings Per Share Calculation [Abstract]
Net income	$ 15,986us-gaap_NetIncomeLoss	$ 15,329us-gaap_NetIncomeLoss	$ 49,248us-gaap_NetIncomeLoss	$ 42,550us-gaap_NetIncomeLoss
Preferred stock dividends	(98)us-gaap_DividendsPreferredStockCash	(83)us-gaap_DividendsPreferredStockCash	(296)us-gaap_DividendsPreferredStockCash	(250)us-gaap_DividendsPreferredStockCash
Income available to common shareholders	$ 15,888	$ 15,246	$ 48,952	$ 42,300
Denominator for earnings per common share calculation:
Weighted average common shares, basic	31,596,000	31,417,000	31,558,000	31,369,000
Effect of dilutive securities:
Preferred stock	760,000	760,000	760,000	760,000
Stock options	481,000	456,000	514,000	438,000
Weighted average number of common shares, diluted	32,837,000	32,633,000	32,832,000	32,567,000
Basic Earnings per common share:	$ 0.50us-gaap_EarningsPerShareBasic	$ 0.49us-gaap_EarningsPerShareBasic	$ 1.55us-gaap_EarningsPerShareBasic	$ 1.35us-gaap_EarningsPerShareBasic
Diluted Earnings per common share:	$ 0.49us-gaap_EarningsPerShareDiluted	$ 0.47us-gaap_EarningsPerShareDiluted	$ 1.50us-gaap_EarningsPerShareDiluted	$ 1.31us-gaap_EarningsPerShareDiluted
Antidilutive securities excluded from computation of earnings per share	153,000	86,000	154,000	98,000

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible preferred stock using the if-converted method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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