Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Income Statement [Abstract]
Revenues	$ 1,957,736	$ 1,573,129
Cost of revenues	1,369,540	1,046,401
Marketing	208,010	194,677
Technology and development	203,508	143,106
General and administrative	127,225	91,489
Operating income	49,453	97,456
Other income (expense):
Interest expense	(35,537)	(26,737)
Interest and other income (expense)	25,963	(32,293)
Income before income taxes	39,879	38,426
Provision for income taxes	12,221	14,730
Net income	$ 27,658	$ 23,696
Earnings per share:
Basic (in dollars per share)	$ 0.06	$ 0.06
Diluted (in dollars per share)	$ 0.06	$ 0.05
Weighted-average common shares outstanding:
Basic (in shares)	428,117	423,624
Diluted (in shares)	437,993	433,809

The aggregate cost of goods produced and sold and services rendered during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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Expenditures for planning and executing the conception, pricing, promotion, and distribution of ideas, goods, and services. Costs of public relations and corporate promotions are typically considered to be marketing costs.

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The net result for the period of deducting operating expenses from operating revenues.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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