Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common stock	Additional Paid In Capital	Accumulated Other Comprehensive Income (Loss)	Treasury stock	Retained Earnings
Beginning Balance at Mar. 31, 2014	$ 409,161	$ 50	$ 273,574	$ 2,772	$ (117,802)	$ 250,567
Beginning Balance (in shares) at Mar. 31, 2014		49,922,959			8,757,175
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	40,338					40,338
Unrealized net investment losses	(54)			(54)
Unrealized net gains on derivative financial instruments	(873)			(873)
Cumulative translation adjustments	(3,397)			(3,397)
Issuance of common stock pursuant to exercise of options	104	$ 0	104
Issuance of common stock pursuant to exercise of options (in shares)		17,850
Issuance of common stock pursuant to vesting of restricted stock units	1	$ 1
Issuance of common stock pursuant to vesting of restricted stock units (in shares)		717,012
Stock-based compensation expense for restricted stock units granted to employees	11,299		11,299
Issuance of common stock under employee stock purchase plan	2,760		2,760
Issuance of common stock under employee stock purchase plan (in shares)		59,897
Repurchase of treasury stock	(31,543)				$ (31,543)
Repurchase of treasury stock (in shares)					743,063
Excess tax benefit from share-based compensation awards	4,322		4,322
Ending Balance at Dec. 31, 2014	432,118	$ 51	292,059	(1,552)	$ (149,345)	290,905
Ending Balance (in shares) at Dec. 31, 2014		50,717,718			9,500,238
Beginning Balance at Mar. 31, 2015	435,750	$ 51	298,101	(4,645)	$ (169,516)	311,759
Beginning Balance (in shares) at Mar. 31, 2015		50,812,548			10,004,743
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(24,753)					(24,753)
Unrealized net investment losses	(67)			(67)
Unrealized net gains on derivative financial instruments	739			739
Cumulative translation adjustments	285			285
Issuance of common stock pursuant to exercise of options	0	$ 0	0
Issuance of common stock pursuant to exercise of options (in shares)		216,547
Issuance of common stock pursuant to vesting of restricted stock units	1	$ 1
Issuance of common stock pursuant to vesting of restricted stock units (in shares)		463,744
Stock-based compensation expense for restricted stock units granted to employees	19,343		19,343
Issuance of common stock under employee stock purchase plan	$ 3,028		3,028
Issuance of common stock under employee stock purchase plan (in shares)	82,836	82,836
Repurchase of treasury stock	$ (212,426)				$ (212,426)
Repurchase of treasury stock (in shares)					5,500,164
Issuance of shares related to the acquisition of the Communications Business of Danaher	2,305,611	$ 62	2,305,549
Issuance of shares related to the acquisition of the Communication business of Danaher (in shares)		62,499,644
Excess tax benefit from share-based compensation awards	1,786		1,786
Ending Balance at Dec. 31, 2015	$ 2,529,297	$ 114	$ 2,627,807	$ (3,688)	$ (381,942)	$ 287,006
Ending Balance (in shares) at Dec. 31, 2015		114,075,319			15,504,907