Consolidated Statements of Operations (Unaudited) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Nov. 30, 2015
Nov. 30, 2014
Nov. 30, 2015
Nov. 30, 2014
NET SALES $ 96,249 $ 96,277 $ 192,961 $ 198,717
COST OF SALES (exclusive of amortization shown separately below) 37,888 35,773 72,529 72,600
GROSS PROFIT 58,361 60,504 120,432 126,117
OPERATING EXPENSES:        
Research and development 6,760 7,115 13,590 14,194
Selling and marketing 14,819 15,373 28,806 30,429
Distribution 4,395 5,316 8,814 10,356
General and administrative 10,608 10,698 21,354 21,581
Amortization expense 13,591 13,651 27,169 27,332
Total operating expenses 50,173 52,153 99,733 103,892
INCOME FROM OPERATIONS 8,188 8,351 20,699 22,225
NON-OPERATING (EXPENSE) INCOME:        
Interest income 41 32 83 88
Interest expense (22,454) (22,822) (44,946) (45,120)
Other, net 78 214 (50) 289
Total non-operating net expense (22,335) (22,576) (44,913) (44,743)
LOSS BEFORE INCOME TAXES (14,147) (14,225) (24,214) (22,518)
BENEFIT FOR INCOME TAXES (2,351) (5,148) (5,201) (7,961)
NET LOSS (11,796) (9,077) (19,013) (14,557)
NET SALES 96,249 96,277 192,961 198,717
COST OF SALES (exclusive of amortization shown separately below) 37,888 35,773 72,529 72,600
GROSS PROFIT $ 58,361 $ 60,504 $ 120,432 $ 126,117