Consolidated Statements of Comprehensive Income (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Net revenue	$ 480.2	$ 421.0
Costs and expenses:
Cost of revenue	161.3	140.4
Research and development	32.0	25.2
Sales and marketing	59.0	57.4
General and administrative	86.6	71.1
Depreciation and amortization	96.9	87.8
Total costs and expenses	435.8	381.9
Income from operations	44.4	39.1
Other income (expense):
Interest expense	(0.4)	(0.5)
Interest and other income (expense)	(2.0)	0.3
Total other income (expense)	(2.4)	(0.2)
Income before income taxes	42.0	38.9
Income taxes	13.6	13.5
Net income	28.4	25.4
Other comprehensive income, net of tax
Foreign currency translation adjustments	(11.2)	2.9
Other comprehensive income (loss)	(11.2)	2.9
Comprehensive income	$ 17.2	$ 28.3
Net income per share
Basic	$ 0.20	$ 0.18
Diluted	$ 0.20	$ 0.18
Weighted average number of shares outstanding
Basic	141.4	141.0
Diluted	144.2	143.8