CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings
Beginning Balance at Dec. 31, 2013	$ 666,090	$ 410	$ (367,121)	$ 750,918	$ 927	$ 280,956
Beginning Balance, shares (in shares) at Dec. 31, 2013		41,042,000
Beginning Balance, Treasury Stock, shares (in shares) at Dec. 31, 2013			(17,814,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adjustment for two-for-one stock split, effective December 21, 2016		$ 410		(410)
Adjustment for two-for-one stock split, effective December 21, 2016 (in shares)		41,042,000
Net income (loss)	34,004					34,004
Other comprehensive income (loss), net of tax	(24,415)				(24,415)
Issuance of common stock through employee stock purchase plan	286	$ 1		285
Issuance of common stock through employee stock purchase plan (in shares)		12,000
Issuance of common stock for vesting of share based awards, net of shares withheld for taxes	13,803	$ 12		13,791
Issuance of common stock for vesting of share based awards, net of shares withheld for taxes (in shares)		1,192,000
Share-based compensation	14,554			14,554
Ending Balance at Dec. 31, 2014	704,322	$ 833	$ (367,121)	779,138	(23,488)	314,960
Ending Balance, shares (in shares) at Dec. 31, 2014		83,288,000
Ending Balance, Treasury Stock, shares (in shares) at Dec. 31, 2014			(17,814,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(3,519)					(3,519)
Other comprehensive income (loss), net of tax	(24,414)
Separation of SeaSpine	(167,229)				(1,667)	(165,562)
Other comprehensive income (loss), net of tax and SeaSpine	$ (22,747)				(22,747)
Treasury Share purchases (in shares)	0		(16,000)
Issuance of common stock	$ 219,680	$ 80		219,600
Issuance of common stock, shares (in shares)		8,006,000
Issuance of common stock through employee stock purchase plan	231			231
Issuance of common stock through employee stock purchase plan (in shares)		8,000
Issuance of common stock for vesting of share based awards, net of shares withheld for taxes	5,255	$ 4		5,251
Issuance of common stock for vesting of share based awards, net of shares withheld for taxes (in shares)		412,000
Share-based compensation	15,450			15,450
Ending Balance at Dec. 31, 2015	$ 751,443	$ 917	$ (367,121)	1,019,670	(47,902)	145,879
Ending Balance, shares (in shares) at Dec. 31, 2015		91,714,000
Ending Balance, Treasury Stock, shares (in shares) at Dec. 31, 2015	(17,830,000)		(17,830,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 74,564					74,564
Other comprehensive income (loss), net of tax	$ (9,252)				(9,252)
Treasury Share purchases (in shares)	0
Treasury shares retirement	$ 0	$ (178)	$ 367,121	(366,943)
Treasury shares retirement (in shares)		(17,830,000)	(17,830,000)
Issuance of common stock through employee stock purchase plan	391	$ 1		390
Issuance of common stock through employee stock purchase plan (in shares)		12,000
Settlement of convertible notes		$ 29		(29)
Settlement of convertible notes (in shares)		2,946,000
Exercise of convertible note hedge	$ (123,100)		$ (123,051)	123,051
Exercise of convertible note hedge (in shares)	(2,946,000)		(2,946,000)
Issuance of common stock for vesting of share based awards, net of shares withheld for taxes	$ 5,211	$ 8		5,203
Issuance of common stock for vesting of share based awards, net of shares withheld for taxes (in shares)		824,000
Share-based compensation	17,310			17,310
Ending Balance at Dec. 31, 2016	$ 839,667	$ 777	$ (123,051)	$ 798,652	$ (57,154)	$ 220,443
Ending Balance, shares (in shares) at Dec. 31, 2016		77,666,000
Ending Balance, Treasury Stock, shares (in shares) at Dec. 31, 2016	(2,946,000)		(2,946,000)