CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 79,871	$ 71,994
Trade accounts receivable, net of allowances of $6,515 and $6,184	126,785	131,918
Inventories, net	233,043	237,114
Deferred tax assets	58,293	58,663
Prepaid expenses and other current assets	23,958	29,632
Total current assets	521,950	529,321
Property, plant and equipment, net	210,111	209,986
Intangible assets, net	447,424	459,459
Goodwill	354,202	363,888
Deferred tax assets	5,684	5,603
Other assets	11,436	10,368
Total assets	1,550,807	1,578,625
Current liabilities:
Borrowings under senior credit facility	5,625	3,750
Accounts payable, trade	42,630	34,060
Deferred revenue	4,303	5,176
Accrued compensation	33,209	40,943
Accrued expenses and other current liabilities	41,038	42,096
Total current liabilities	126,805	126,025
Long-term borrowings under senior credit facility	396,250	413,125
Long-term convertible securities	215,177	213,121
Deferred tax liabilities	92,431	91,623
Other liabilities	32,045	30,409
Total liabilities	862,708	874,303
Commitments and contingencies
Stockholders’ equity:
Preferred stock; no par value; 15,000 authorized shares; none outstanding	0	0
Common stock; $0.01 par value; 60,000 authorized shares; 41,755 and 41,644 issued at March 31, 2015 and December 31, 2014, respectively	418	416
Additional paid-in capital	779,074	779,555
Treasury stock, at cost; 8,903 shares at March 31, 2015 and December 31, 2014	(367,121)	(367,121)
Accumulated other comprehensive loss	(47,616)	(23,488)
Retained earnings	323,344	314,960
Total stockholders’ equity	688,099	704,322
Total liabilities and stockholders’ equity	$ 1,550,807	$ 1,578,625