Consolidated Statements of Cash Flows - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2016	Mar. 31, 2015
Operating activities
Net loss		$ (45,596)	$ (10,455)
Less: Income (loss) from discontinued operations		0	6,284
Loss from continuing operations		(45,596)	(16,739)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:
Depreciation, Depletion and Amortization		30,143	26,266
Amortization of acquired intangible assets		4,654	5,934
Share-based Compensation	[1]	30,756	35,144
Restructuring Costs and Asset Impairment Charges		45	0
Deferred income taxes		(2,310)	22
Gain from changes in fair value of contingent consideration	[2]	3,442	(279)
Fair Value, Option, Changes in Fair Value, Gain (Loss)		1,100	0
Change in assets and liabilities, net of acquisitions:
Restricted cash		505	3,245
Accounts receivable		(3,223)	(8,901)
Prepaid expenses and other current assets		20,940	(2,513)
Accounts payable		(2,850)	2,244
Accrued merchant and supplier payables		(112,425)	(17,034)
Accrued expenses and other current liabilities		10,848	(2,470)
Other, net		(12,754)	18,688
Net cash provided by (used in) operating activities from continuing operations		(76,725)	43,607
Net cash used in operating activities from discontinued operations		0	(24,355)
Net cash provided by (used in) operating activities		(76,725)	19,252
Investing activities
Purchases of property and equipment and capitalized software		(19,952)	(18,294)
Acquisitions of businesses, net of acquired cash		(40)	(800)
Settlements of liabilities related to purchase of additional interest in consolidated subsidiary		0	(349)
Purchases of intangible assets		(786)	0
Net cash used in investing activities from continuing operations		(20,778)	(19,443)
Net cash used in investing activities from discontinued operations		0	(624)
Net cash used in investing activities		(20,778)	(20,067)
Financing activities
Payments for purchases of treasury stock		(64,665)	(18,006)
Taxes paid related to net share settlements of stock-based compensation awards		(4,964)	(14,584)
Proceeds from stock option exercises and employee stock purchase plan		1,933	1,946
Partnership distribution payments to noncontrolling interest holders		(3,365)	(1,558)
Payments of capital lease obligations		(6,954)	(3,636)
Net cash used in financing activities		(78,015)	(35,838)
Effect of exchange rate changes on cash and cash equivalents		10,668	(30,199)
Net decrease in cash and cash equivalents, including cash classified within current assets held for sale		(164,850)	(66,852)
Less: Increase in cash and cash equivalents classified within current assets held for sale		0	(25,722)
Net decrease in cash and cash equivalents		(164,850)	(41,130)
Cash and cash equivalents, beginning of period		853,362	1,016,634
Cash and cash equivalents, end of period		688,512	975,504
Non-cash investing and financing activities
Equipment acquired under capital lease obligations		1,163	0
Payments for Tenant Improvements		4,809	0
Liability for purchases of treasury stock		2,965	901
Liability for purchase consideration		250	0
Liability for purchase of additional interests in consolidated subsidiaries		526	1,249
Continuing Operations [Member]
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:
Share-based Compensation		30,800	35,100
Non-cash investing and financing activities
Accounts payable and accrued expenses related to purchases of property and equipment and capitalized software		3,928	3,440
Discontinued Operations [Abstract]
Accounts payable and accrued expenses related to purchases of property and equipment and capitalized software		3,928	3,440
Discontinued Operations [Member]
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:
Share-based Compensation			1,100
Non-cash investing and financing activities
Accounts payable and accrued expenses related to purchases of property and equipment and capitalized software		0	415
Discontinued Operations [Abstract]
Accounts payable and accrued expenses related to purchases of property and equipment and capitalized software		$ 0	$ 415

[1] Includes stock-based compensation classified within cost of revenue, marketing expense, selling, general and administrative expense and restructuring charges. Other income (expense), net, includes $0.2 million of additional stock-based compensation for the three months ended March 31, 2016.

[2] Changes in the fair value of contingent consideration liabilities are classified within "Acquisition-related expense (benefit), net" on the condensed consolidated statements of operations.