Condensed Consolidating Financial Statements Cash Flow (Details) - USD ($) $ in Thousands	6 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Operating Activities:
Net cash provided by (used in) operating activities	$ 23,043	$ (10,932)
Investing activities:
Capital expenditures	(10,344)	(9,268)
Proceeds from sale of assets	0	247
Acquisitions, net of cash received	0	(2,892)
Net cash provided by (used in) investing activities	(10,344)	(11,913)
Financing activities:
Proceeds from revolving line of credit	0	8,000
Payments of revolving line of credit	0	(3,500)
Payments on long-term debt	(1,870)	(481)
Purchase of treasury stock	(628)	(575)
Net cash provided by (used in) financing activities	(2,498)	3,444
Net increase (decrease) in cash and cash equivalents	10,201	(19,401)
Effect of Exchange Rate on Cash and Cash Equivalents [Abstract]
Effect of foreign currency fluctuations on cash	(452)	354
Cash and cash equivalents at beginning of fiscal period	65,004	56,362
Cash and cash equivalents at end of fiscal period	74,753	37,315
Reclassifications and Eliminations
Operating Activities:
Net cash provided by (used in) operating activities	0	0
Investing activities:
Capital expenditures	0	0
Proceeds from sale of assets		0
Acquisitions, net of cash received		0
Net cash provided by (used in) investing activities	0	0
Financing activities:
Proceeds from revolving line of credit		0
Payments of revolving line of credit		0
Payments on long-term debt	0	0
Purchase of treasury stock	0	0
Net cash provided by (used in) financing activities	0	0
Net increase (decrease) in cash and cash equivalents	0	0
Effect of Exchange Rate on Cash and Cash Equivalents [Abstract]
Effect of foreign currency fluctuations on cash	0	0
Cash and cash equivalents at beginning of fiscal period	0
Cash and cash equivalents at end of fiscal period	0	0
Parent
Operating Activities:
Net cash provided by (used in) operating activities	2,481	575
Investing activities:
Capital expenditures	0	0
Proceeds from sale of assets		0
Acquisitions, net of cash received		0
Net cash provided by (used in) investing activities	0	0
Financing activities:
Proceeds from revolving line of credit		0
Payments of revolving line of credit		0
Payments on long-term debt	(1,870)	0
Purchase of treasury stock	(628)	(575)
Net cash provided by (used in) financing activities	(2,498)	(575)
Net increase (decrease) in cash and cash equivalents	(17)	0
Effect of Exchange Rate on Cash and Cash Equivalents [Abstract]
Effect of foreign currency fluctuations on cash	0	0
Cash and cash equivalents at beginning of fiscal period	640
Cash and cash equivalents at end of fiscal period	623	640
Guarantor Subsidiaries
Operating Activities:
Net cash provided by (used in) operating activities	14,940	(6,284)
Investing activities:
Capital expenditures	(2,750)	(4,630)
Proceeds from sale of assets		247
Acquisitions, net of cash received		(2,892)
Net cash provided by (used in) investing activities	(2,750)	(7,275)
Financing activities:
Proceeds from revolving line of credit		6,000
Payments of revolving line of credit		(3,500)
Payments on long-term debt	0	0
Purchase of treasury stock	0	0
Net cash provided by (used in) financing activities	0	2,500
Net increase (decrease) in cash and cash equivalents	12,190	(11,059)
Effect of Exchange Rate on Cash and Cash Equivalents [Abstract]
Effect of foreign currency fluctuations on cash	0	0
Cash and cash equivalents at beginning of fiscal period	36,209
Cash and cash equivalents at end of fiscal period	48,399	22,035
Non-Guarantor Subsidiaries
Operating Activities:
Net cash provided by (used in) operating activities	5,622	(5,223)
Investing activities:
Capital expenditures	(7,594)	(4,638)
Proceeds from sale of assets		0
Acquisitions, net of cash received		0
Net cash provided by (used in) investing activities	(7,594)	(4,638)
Financing activities:
Proceeds from revolving line of credit		2,000
Payments of revolving line of credit		0
Payments on long-term debt	0	(481)
Purchase of treasury stock	0	0
Net cash provided by (used in) financing activities	0	1,519
Net increase (decrease) in cash and cash equivalents	(1,972)	(8,342)
Effect of Exchange Rate on Cash and Cash Equivalents [Abstract]
Effect of foreign currency fluctuations on cash	(452)	354
Cash and cash equivalents at beginning of fiscal period	28,155
Cash and cash equivalents at end of fiscal period	$ 25,731	$ 14,640