Goodwill and Intangible Assets (Tables)

3 Months Ended

Mar. 31, 2020

Goodwill and Intangible Assets Disclosure [Abstract]

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

The table below presents changes to the carrying amount of goodwill by segment during the three months ended March 31, 2020 (in thousands).

	Research		Conferences		Consulting		Total
Balance at December 31, 2019 (1)	$	2,651,060	$	189,641	$	97,025	$	2,937,726
Foreign currency translation impact	(8,718)		(1,278)		(64)		(10,060)
Balance at March 31, 2020	$	2,642,342	$	188,363	$	96,961	$	2,927,666

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

Schedule of amortizable intangible assets

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

March 31, 2020	Customer Relationships		Software		Content		Other		Total
Gross cost at December 31, 2019	$	1,145,109	$	111,033	$	14,140	$	30,838	$	1,301,120
Foreign currency translation impact	(36,507)		(1,171)		(175)		(72)		(37,925)
Gross cost	1,108,602		109,862		13,965		30,766		1,263,195
Accumulated amortization (1)	(299,121)		(66,478)		(12,302)		(21,144)		(399,045)
Balance at March 31, 2020	$	809,481	$	43,384	$	1,663	$	9,622	$	864,150

December 31, 2019	Customer Relationships		Software		Content		Other		Total
Gross cost	$	1,145,109	$	111,033	$	14,140	$	30,838	$	1,301,120
Accumulated amortization (1)	(283,369)		(61,564)		(11,225)		(19,875)		(376,033)
Balance at December 31, 2019	$	861,740	$	49,469	$	2,915	$	10,963	$	925,087

(1) Finite-lived intangible assets are amortized using the straight-line method over the following periods: Customer relationships—4 to 13 years; Software—3 to 7 years; Content—1.5 to 4 years; and Other—2 to 11 years.

Schedule of estimated future amortization expense by year

The estimated future amortization expense by year for finite-lived intangible assets is presented in the table below (in thousands).

2020 (remaining nine months)	$	91,192
2021	102,091
2022	92,339
2023	92,323
2024	87,064
Thereafter	399,141
	$	864,150