LONG-TERM DEBT: (Details) (USD $)	12 Months Ended						0 Months Ended	12 Months Ended	0 Months Ended			12 Months Ended				12 Months Ended							12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2014 March 10, 2014 derivative agreement Cash flow hedge Other, net	Mar. 31, 2012 Interest rate swap July 25, 2011 derivative agreement	Mar. 31, 2012 Interest rate swap July 25, 2011 derivative agreement Cash flow hedge	Mar. 10, 2014 Interest rate swap March 10, 2014 derivative agreement Cash flow hedge	Mar. 31, 2014 Interest rate swap March 10, 2014 derivative agreement Cash flow hedge	Oct. 09, 2013 Term loan credit agreement	Mar. 31, 2014 Term loan credit agreement	Mar. 31, 2013 Term loan credit agreement	Mar. 31, 2014 Term loan credit agreement Quarterly installments payable through September 2014	Mar. 31, 2014 Term loan credit agreement Quarterly installments payable through September 2017	Mar. 31, 2014 Term loan credit agreement Quarterly installments payable through June 2018	Mar. 31, 2014 Term loan credit agreement Final payment due on October 9, 2018	Mar. 31, 2014 Term loan credit agreement LIBOR	Mar. 31, 2014 Capital leases and installment payment obligations	Mar. 31, 2013 Capital leases and installment payment obligations	Mar. 31, 2014 Other debt and long-term liabilities	Mar. 31, 2013 Other debt and long-term liabilities	Mar. 31, 2014 Revolving credit facility	Mar. 31, 2013 Revolving credit facility	Mar. 31, 2014 Revolving credit facility LIBOR	Mar. 31, 2014 Revolving credit facility Alternative base rate
Long-term debt
Total long-term debt and capital leases	$ 317,610,000	$ 253,505,000								$ 292,500,000	$ 218,000,000						$ 12,990,000	$ 21,368,000	$ 12,120,000	$ 14,137,000
Less current installments	28,567,000	16,105,000
Long-term debt, excluding current installments	289,043,000	237,400,000
Long-term debt stated interest rate percentage, minimum																	3.00%	3.00%
Long-term debt stated interest rate percentage, maximum																	8.00%	8.00%
Maximum remaining maturity period of debt																	8 years	8 years
Amount borrowed									300,000,000
Existing debt repaid with proceeds of term loan	235,895,000	26,871,000	154,876,000						215,000,000
Payment of fees related to the new credit agreement	4,370,000								4,400,000
Aggregate amount of borrowing commitment										300,000,000											300,000,000
Required quarterly installment payments												3,800,000	7,500,000	11,300,000
Final payment of long-term debt															161,300,000
Long-term debt variable interest rate description																LIBOR							LIBOR	Alternative base rate
Long-term debt basis spread on variable interest rate (as a percent)																2.00%							2.00%
Weighted-average interest rate on long-term debt (as a percent)										2.40%
Outstanding revolving credit borrowings																					0	0
Outstanding letters of credit																					2,200,000
Revolving credit facility dividend restrictions amount, maximum																					30,000,000
Fixed interest rate payable on swap (as a percent)					0.94%		0.98%
Notional amount of derivative						150,000,000	50,000,000
Description of variable interest rate basis receivable on swap					LIBOR		LIBOR
LIBOR rate (as a percent)								0.23%
Amount of ineffectiveness								0
Fair market value of the derivative							0
Unrealized loss of the derivative recorded in other comprehensive income (loss)				$ 20,000