Goodwill and Intangible Assets (Tables)

6 Months Ended

Jun. 30, 2017

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of changes to the carrying amount of goodwill by reporting unit

The following table presents changes to the carrying amount of goodwill by reportable segment during the six months ended June 30, 2017 (in thousands):

	Research		Consulting		Events		Talent Assessment & Other			Total
Balance at December 31, 2016 (1)	$	595,450	$	96,480	$	46,523	$	—		$	738,453
Additions due to acquisitions (2)	1,883,493		—		148,737		395,744			2,427,974
Foreign currency translation impact	4,051		469		197		(1,251		)	3,466
Balance at June 30, 2017	$	2,482,994	$	96,949	$	195,457	$	394,493		$	3,169,893

(1) The Company does not have any accumulated goodwill impairment losses.

(2) The goodwill additions are due to the acquisitions of CEB and L2 during April 2017 and March 2017, respectively (see Note 2 for additional information regarding our recent acquisitions).

Schedule of amortizable intangible assets

The following tables present reconciliations of the carrying amounts of the Company's finite-lived intangible assets as of the dates indicated (in thousands):

June 30, 2017	Trade Names			Customer Relationships			Content			Software			Non-Competes			Total
Gross cost at December 31, 2016	$	4,337		$	63,369		$	3,728		$	16,025		$	29,308		$	116,767
Additions due to acquisitions (1)	14,390			1,251,000			143,500			181,000			—			1,589,890
Foreign currency translation impact	51			478			(1,904		)	(692		)	55			(2,012		)
Gross cost	18,778			1,314,847			145,324			196,333			29,363			1,704,645
Accumulated amortization (2)	(4,729		)	(47,316		)	(20,678		)	(22,949		)	(13,597		)	(109,269		)
Balance at June 30, 2017	$	14,049		$	1,267,531		$	124,646		$	173,384		$	15,766		$	1,595,376

December 31, 2016	Trade Names			Customer Relationships			Content			Software			Non-Competes			Total
Gross cost	$	4,337		$	63,369		$	3,728		$	16,025		$	29,308		$	116,767
Accumulated amortization (2)	(1,737		)	(16,744		)	(2,033		)	(8,904		)	(10,548		)	(39,966		)
Balance at December 31, 2016	$	2,600		$	46,625		$	1,695		$	7,121		$	18,760		$	76,801

(1) The additions were primarily due to the acquisitions of CEB and L2 during April 2017 and March 2017, respectively (see Note 2 for additional information regarding our recent acquisitions).

(2) Finite-lived intangible assets are amortized using the straight-line method over the following periods: Trade names—1.5 to 4 years; Customer relationships—4 to 13 years ; Content—1.5 to 4 years; Software—3 to 6 years; and Non-competes—3 to 5 years.

Schedule of estimated future amortization expense by year

The estimated future amortization expense by year for finite-lived intangible assets will be as follows (in thousands):

2017 (remaining six months)	$	130,281
2018	240,770
2019	179,824
2020	138,568
2021	117,752
Thereafter	788,181
	$	1,595,376