Consolidated Statements of Cash Flows (USD $)	12 Months Ended
	Feb. 28, 2015	Feb. 28, 2014	Feb. 28, 2013
Cash Flows From Operating Activities:
Net Income	$ 64,943,000	$ 59,597,000	$ 60,456,000
Adjustments To Reconcile Net Income To Net Cash Provided By Operating Activities:
Depreciation	28,100,000	25,100,000	19,400,000
Depreciation, Amortization and Accretion, Net	46,089,000	43,305,000	29,363,000
Deferred income tax expense	15,818,000	842,000	3,366,000
Share-based compensation expense	4,080,000	3,703,000	3,175,000
Amortization of deferred borrowing costs	1,431,000	1,421,000	287,000
Provision for doubtful accounts	458,000	(116,000)	446,000
Gain (Loss) on Disposition of Assets	2,651,000	0	0
Net (gain) loss on insurance settlement or sale of property, plant and equipment	(2,525,000)	(8,039,000)	(8,303,000)
Effects of changes in operating assets and liabilities, net of acquisitions:
Accounts Receivable	(9,382,000)	35,955,000	(11,599,000)
Inventories	(879,000)	(6,209,000)	(4,454,000)
Prepaid expenses and other assets	5,543,000	(6,590,000)	(2,244,000)
Net change in billings related to costs and estimated earnings on uncompleted contracts	(5,635,000)	(9,732,000)	1,942,000
Accounts payable	11,025,000	(4,150,000)	958,000
Other accrued liabilities and income taxes payable	(15,460,000)	(2,712,000)	19,345,000
Net cash provided by operating activities:	118,157,000	107,275,000	92,738,000
Cash flows from investing activities:
Proceeds from the sale or insurance settlement of property, plant, and equipment	1,330,000	8,205,000	11,839,000
Acquisition of subsidiaries, net of cash acquired	(11,518,000)	(275,702,000)	(137,058,000)
Purchases of property, plant and equipment	(29,377,000)	(43,472,000)	(24,923,000)
Net cash used in investing activities:	(39,565,000)	(310,969,000)	(150,142,000)
Cash flows from financing activities:
Tax benefits from stock options exercised	259,000	1,602,000	1,283,000
Proceeds from exercise of stock options and stock appreciation rights	0	0	16,000
Payments on revolving loan	(57,905,000)	(60,000,000)	0
Proceeds from Lines of Credit	10,977,000	197,000,000	0
Proceeds from Issuance of Long-term Debt	0	75,000,000	0
Proceeds from long-term debt	(20,848,000)	(17,098,000)	(18,136,000)
Cash dividends paid	(14,897,000)	(14,290,000)	(13,423,000)
Net cash provided by (used in) financing activities	(82,414,000)	176,333,000	(30,360,000)
Effect of exchange rate changes on cash	(1,216,000)	(672,000)	59,000
Net increase (decrease) in cash and cash equivalents	(5,038,000)	(28,033,000)	(87,705,000)
Cash and cash equivalents at beginning of year	27,565,000	55,598,000	143,303,000
Cash and cash equivalents at end of year	22,527,000	27,565,000	55,598,000
Cash paid during the year for:
Interest	15,613,000	16,500,000	13,108,000
Income taxes	15,264,000	26,332,000	30,967,000
Payments of Debt Issuance Costs	$ 0	$ (5,881,000)	$ (100,000)