INCOME TAXES (Details) (USD $)	12 Months Ended
	Mar. 31, 2014		Mar. 31, 2013		Mar. 31, 2012
Current:
Federal	$ 28,859,000		$ 25,530,000		$ 23,844,000
State	1,263,000		2,452,000		2,719,000
Foreign	4,384,000		4,777,000		5,080,000
Total current provision for income taxes	34,506,000		32,759,000		31,643,000
Deferred [Abstract]
Federal	(4,675,000)		(586,000)		2,324,000
State	(629,000)		(474,000)		(569,000)
Foreign	(480,000)		324,000		168,000
Total deferred benefit for income taxes	(5,784,000)		(736,000)		1,923,000
Income tax expense	28,722,000		32,023,000		33,566,000
Components of income before income taxes
United States	85,231,000		80,875,000		79,589,000
Foreign	55,908,000		57,550,000		63,013,000
Income before income taxes	141,139,000		138,425,000		142,602,000
Reconciliation between statutory federal income taxes and income tax expense
Tax expense at statutory rate	49,399,000		48,449,000		49,911,000
Foreign operations taxed at different rates	(16,175,000)		(15,244,000)		(16,973,000)
State taxes, net of federal benefit	634,000		1,978,000		2,149,000
Research and development credit	(1,805,000)		(3,380,000)		(1,392,000)
Other, net	(3,331,000)		220,000		(129,000)
Income tax expense	28,722,000		32,023,000		33,566,000
Effective tax rate	20.40%		23.10%		23.50%
Permanently reinvested foreign earnings	594,200,000
Components of Deferred Tax Assets [Abstract]
Accruals and other reserves	8,459,000		7,983,000
Net operating loss carry forward	4,580,000		5,956,000
Stock compensation	8,957,000		8,199,000
Other deferred tax assets	3,937,000		3,643,000
Valuation allowance	(3,351,000)		(5,984,000)
Total deferred tax assets	22,582,000		19,797,000
Components of Deferred Tax Liabilities [Abstract]
Deferred gains on sales of properties	(1,756,000)		(1,756,000)
Unremitted earnings of certain subsidiaries	(3,064,000)		(3,064,000)
Fixed asset depreciation	(3,571,000)		(4,402,000)
Other deferred tax liabilities	0		(2,197,000)
Total deferred tax liabilities	(8,391,000)		(11,419,000)
Net deferred tax assets	14,191,000	[1]	8,378,000	[1]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of period	11,072,000		11,141,000		10,458,000
Increase (decrease) of unrecognized tax benefits related to prior years	641,000		(117,000)		116,000
Increase of unrecognized tax benefits related to the current year	2,427,000		2,430,000		2,074,000
Reductions to unrecognized tax benefits related to lapse of applicable statute of limitations	(1,569,000)		(2,382,000)		(1,507,000)
Balance at end of period	12,571,000		11,072,000		11,141,000
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	1,700,000		2,000,000
Accrued penalties related to unrecognized tax benefits	$ 0		$ 0

[1] The long-term portion of the Company's deferred tax assets for the fiscal year ending March 31, 2014 is included as a component of other assets in the consolidated balance sheets.