CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Cash flows from operating activities:
Net income	$ 114,394	$ 5,710	$ 122,265
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion	48,572	52,628	50,024
Change in fair value of contingent consideration	0	0	(4,411)
Bad debt expense	4,168	2,847	5,120
Deferred tax expense (benefit)	8,138	(24,495)	8,167
Stock-based compensation	14,302	6,175	6,622
Excess tax benefits from stock compensation	1,945	100	471
Loss (gain) on sale of assets	387	538	(1,338)
Impairment of goodwill	0	113,944	0
Impairment of intangible and other long-lived assets	2,417	13,222	9,773
Restructuring charges	1,667	28,984	24,673
Changes in operating assets and liabilities:
Trade accounts receivable, net	10,770	(1,336)	(23,545)
Inventories, net	(751)	1,060	(61,492)
Prepaid expenses and other current assets	11,124	7,975	(3,681)
Income tax receivable	26,999	(1,331)	(8,286)
Other assets	(1,714)	2,257	(3,082)
Trade accounts payable	(2,184)	(7,825)	14,775
Contingent consideration	0	0	(819)
Accrued expenses	28,627	(403)	(16,221)
Income taxes payable	(3,638)	(3,743)	(397)
Long-term liabilities	62,128	3,023	7,195
Net cash provided by operating activities	327,351	199,330	125,813
Cash flows from investing activities:
Purchases of property and equipment, net	(34,813)	(44,499)	(66,186)
Proceeds from sales of property and equipment, net	116	0	830
Purchases of tangible, intangible, and other assets, net	0	0	(4,700)
Proceeds from sale of net assets	0	0	2,835
Net cash used in investing activities	(34,697)	(44,499)	(67,221)
Cash flows from financing activities:
Proceeds from short-term borrowings	214,751	405,988	449,200
Repayments of short-term borrowings	(214,889)	(468,938)	(387,120)
Proceeds on issuance of stock for employee stock purchase plan	765	798	0
Cash paid for shares withheld for taxes	(8,105)	(8,452)	(3,691)
Cash paid for repurchases of common stock	(149,687)	(12,572)	(94,200)
Contingent consideration paid	0	(20,058)	(445)
Loan origination costs on short-term borrowings	0	0	(62)
Repayment of mortgage principal	(550)	(523)	(493)
Net cash used in financing activities	(157,715)	(103,757)	(36,811)
Effect of foreign currency exchange rates on cash	3,267	(5,266)	(968)
Net change in cash and cash equivalents	138,206	45,808	20,813
Cash and cash equivalents at beginning of period	291,764	245,956	225,143
Cash and cash equivalents at end of period	429,970	291,764	245,956
Cash paid during the period for:
Income taxes paid, net of refunds ($23,133, $17,132 and $501 as of March 31, 2018, 2017 and 2016, respectively)	14,407	14,099	29,916
Income tax refunds	23,133	17,132	501
Interest	3,774	5,494	4,640
Non-cash investing and financing activities:
Accrued for purchases of property and equipment	2,020	1,101	2,640
Accrued for asset retirement obligations	1,359	2,359	1,394
Accrued for shares withheld for taxes	$ 171	$ 0	$ 919