Unrestricted Subsidiaries Unrestricted Subsidiaries (Financial Position) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Cash and cash equivalents	$ 415,930		$ 433,663	$ 591,881	$ 207,801
Accounts receivable	87,319		91,699
Prepaid expenses and other current assets	27,140		22,602
Deferred income taxes	4,514		2,013
Total current assets	632,091		646,183
Property and equipment, net	36,778		38,217
Tradenames, net	103,843		105,551
Patent and patent licenses, net	21,857		24,927
Customer Relationships, Net	175,488		163,766
Goodwill	674,084		635,675
Other purchased intangibles, net	14,980		17,556
Other assets	13,511		12,819
Total assets	1,726,809		1,705,202
Accounts payable and accrued expenses	87,081		95,310
Income taxes payable	1,215		0
Deferred revenue, current	75,353		63,457
Deferred Tax Liabilities, Net, Current	362		342
Total current liabilities	164,335		159,367
Deferred income taxes	63,267		61,960
Other long-term liabilities	19,242		22,416
Total liabilities	$ 877,606		$ 884,967
Commitments and contingencies
Common Stock, Value, Issued	$ 476		$ 474
Additional paid-in capital	282,702		273,304
Retained Earnings (Accumulated Deficit)	584,831		553,584
Accumulated Other Comprehensive Income (Loss), Net of Tax	(18,806)	$ (21,984)	(7,127)
Total liabilities and stockholders’ equity	1,726,809		1,705,202
Unrestricted Subsidiaries [Member]
Cash and cash equivalents	55,796		27,944
Accounts receivable	51,295		57,005
Prepaid expenses and other current assets	2,785		2,986
Deferred income taxes	5,829		5,292
Total current assets	115,705		93,227
Property and equipment, net	13,408		12,834
Tradenames, net	67,038		70,310
Patent and patent licenses, net	21,013		24,007
Customer Relationships, Net	49,779		55,925
Goodwill	241,328		245,613
Other purchased intangibles, net	7,114		8,901
Other assets	1,654		1,706
Total assets	517,039		512,523
Accounts payable and accrued expenses	42,389		40,296
Income taxes payable	0		316
Deferred revenue, current	5,990		5,277
Total current liabilities	48,379		45,889
Deferred income taxes	18,224		17,397
Other long-term liabilities	15,100		16,243
Total liabilities	191,703		189,529
Additional paid-in capital	318,810		317,932
Retained Earnings (Accumulated Deficit)	7,780		6,051
Accumulated Other Comprehensive Income (Loss), Net of Tax	(1,254)		(989)
Stockholders' Equity Attributable to Parent	325,336		322,994
Total liabilities and stockholders’ equity	517,039		512,523
Notes Payable, Related Parties, Noncurrent	$ 110,000		$ 110,000