Basis of Presentations and Summary of Significant Accounting Policies - Additional Information (Details) $ in Thousands		1 Months Ended		3 Months Ended		12 Months Ended
	Aug. 01, 2014	Feb. 28, 2015 USD ($)	Aug. 31, 2014	Sep. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) item	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Basis Of Presentation And Significant Accounting Policies [Line Items]
Reverse stock split of common stock and treasury stock	0.2		0.2
Other income, net						$ 3,107	$ 654	$ 13
Property and equipment, net						14,568	22,836
Accumulated amortization						45,607	65,410
Unrealized gains on marketable securities available-for-sale								900
Reclassification from other comprehensive income of unrealized gains on marketable securities					$ 900
Recognized realized gains							1,400
Cash received from disposal of businesses and properties, net of cash disposed						$ 5,071	13,696
Accounts receivable, past due time period individual account reviewed for collectibility						60 days
Impairment losses						$ 0
Number of reporting units | item						2
Goodwill impairment charge				$ 232,300		$ 0	232,270
Goodwill						10,358	10,358	347,382
Advertising expense						1,900	2,200	2,500
Gain Loss On Sale Of Business						(3,156)	(795)
Content And Media
Basis Of Presentation And Significant Accounting Policies [Line Items]
Goodwill impairment charge							232,300
Fair value of goodwill				$ 0			0
Marketplaces
Basis Of Presentation And Significant Accounting Policies [Line Items]
Goodwill						$ 10,400
Media content
Basis Of Presentation And Significant Accounting Policies [Line Items]
Intangibles, useful life						5 years
Amortization of intangible assets						$ 3,400	7,700	$ 3,100
Computer and Other Related Equipment
Basis Of Presentation And Significant Accounting Policies [Line Items]
Property and equipment, useful life						3 years
Software
Basis Of Presentation And Significant Accounting Policies [Line Items]
Property and equipment, net						$ 7,200	12,000
Accumulated amortization						$ 15,600	$ 24,700
Furniture and Fixtures
Basis Of Presentation And Significant Accounting Policies [Line Items]
Property and equipment, useful life						5 years
Minimum | Software
Basis Of Presentation And Significant Accounting Policies [Line Items]
Property and equipment, useful life						2 years
Minimum | Leasehold Improvements
Basis Of Presentation And Significant Accounting Policies [Line Items]
Property and equipment, useful life						1 year
Maximum | Software
Basis Of Presentation And Significant Accounting Policies [Line Items]
Property and equipment, useful life						3 years
Maximum | Leasehold Improvements
Basis Of Presentation And Significant Accounting Policies [Line Items]
Property and equipment, useful life						10 years
Advertising Service Providers | Minimum | Invoice Generated Monthly Billed
Basis Of Presentation And Significant Accounting Policies [Line Items]
Accounts receivable, days outstanding						30 days
Advertising Service Providers | Maximum | Invoice Generated Monthly Billed
Basis Of Presentation And Significant Accounting Policies [Line Items]
Accounts receivable, days outstanding						60 days
Content Sales | Minimum
Basis Of Presentation And Significant Accounting Policies [Line Items]
Accounts receivable, days outstanding						30 days
Content Sales | Maximum
Basis Of Presentation And Significant Accounting Policies [Line Items]
Accounts receivable, days outstanding						60 days
Direct Advertisers | Minimum
Basis Of Presentation And Significant Accounting Policies [Line Items]
Accounts receivable, days outstanding						30 days
Direct Advertisers | Maximum
Basis Of Presentation And Significant Accounting Policies [Line Items]
Accounts receivable, days outstanding						60 days
Syndicated Content Customers | Maximum
Basis Of Presentation And Significant Accounting Policies [Line Items]
Accounts receivable, days outstanding						30 days
Pluck Social Media
Basis Of Presentation And Significant Accounting Policies [Line Items]
Cash received from disposal of businesses and properties, net of cash disposed		$ 3,800
Gain Loss On Sale Of Business		$ 2,100
Common Stock
Basis Of Presentation And Significant Accounting Policies [Line Items]
Reverse stock split of common stock and treasury stock						0.20