CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Sep. 30, 2015	Mar. 31, 2015
Statement of Financial Position [Abstract]
Trade accounts receivable, allowances (in dollars)	$ 24,526	$ 18,218
Accumulated depreciation	143,965	129,002
Accumulated amortization	$ 41,482	$ 37,316
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized shares	125,000	125,000
Common stock, issued shares	32,331	33,292
Common stock, outstanding shares	32,331	33,292