Goodwill and Acquired Intangible Assets (Tables)

6 Months Ended

Jun. 30, 2015

Goodwill And Intangible Assets Disclosure [Abstract]

Components of Acquired Intangible Assets (Finite Lived)

The components of acquired intangible assets as of June 30, 2015 and December 31, 2014 were as follows:

	June 30, 2015							December 31, 2014
	Gross Carrying Amount		Accumulated Amortization			NetCarrying Value		GrossCarrying Amount		Accumulated Amortization			NetCarrying Value
	(in thousands)
Developed technology	$	8,438	$	(4,174	)	$	4,264	$	5,143	$	(2,392	)	$	2,751
Customer and vendor relationships, databases		227,583		(36,985	)		190,598		191,979		(30,067	)		161,912
Trademarks		372		(89	)		283		—		—			—
Total amortizable intangible assets		236,393		(41,248	)		195,145		197,122		(32,459	)		164,663
Indefinite-lived trademarks		89,676		—			89,676		89,676		—			89,676
Total acquired intangible assets	$	326,069	$	(41,248	)	$	284,821	$	286,798	$	(32,459	)	$	254,339

The components of the acquired intangibles assets added during the six months ended June 30, 2015 were as follows:

	Six Months Ended June 30, 2015		Weighted-Average Amortization Period
		(in thousands)		(years)
Customer and vendor relationships	$	35,604		18.4
Developed technology		3,295		1.5
Trademarks		372		1.7
Total	$	39,271

Components of Acquired Intangible Assets (Infinite Lived)

The components of acquired intangible assets as of June 30, 2015 and December 31, 2014 were as follows:

	June 30, 2015							December 31, 2014
	Gross Carrying Amount		Accumulated Amortization			NetCarrying Value		GrossCarrying Amount		Accumulated Amortization			NetCarrying Value
	(in thousands)
Developed technology	$	8,438	$	(4,174	)	$	4,264	$	5,143	$	(2,392	)	$	2,751
Customer and vendor relationships, databases		227,583		(36,985	)		190,598		191,979		(30,067	)		161,912
Trademarks		372		(89	)		283		—		—			—
Total amortizable intangible assets		236,393		(41,248	)		195,145		197,122		(32,459	)		164,663
Indefinite-lived trademarks		89,676		—			89,676		89,676		—			89,676
Total acquired intangible assets	$	326,069	$	(41,248	)	$	284,821	$	286,798	$	(32,459	)	$	254,339

The components of the acquired intangibles assets added during the six months ended June 30, 2015 were as follows:

	Six Months Ended June 30, 2015		Weighted-Average Amortization Period
		(in thousands)		(years)
Customer and vendor relationships	$	35,604		18.4
Developed technology		3,295		1.5
Trademarks		372		1.7
Total	$	39,271

Changes in Carrying Amount of Goodwill

Changes in the carrying amount of goodwill for the six months ended June 30, 2015 were as follows:

	Goodwill		Accumulated Impairment Losses		Net Book Value
	(in thousands)
Balance as of December 31, 2014	$	352,788		—	$	352,788
Acquisitions		34,778		—		34,778
Balance as of June 30, 2015	$	387,566	$	—	$	387,566

Estimated Future Amortization of Acquired Intangible Assets

Estimated future amortization expense of acquired intangible assets as of June 30, 2015 was as follows:

	(in thousands)
The remainder of 2015	$	9,347
2016		16,461
2017		14,193
2018		14,022
2019		12,610
Thereafter		128,512
Total	$	195,145