Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 152,822	$ 105,185
Accounts receivable (less allowance for credit losses of $7,236 and $7,161 as of March 31, 2020 and December 31, 2019, respectively)	285,528	281,392
Prepaid expenses and other current assets	54,453	59,972
Total current assets	492,803	446,549
Property and equipment, net	443,998	451,021
Operating lease assets	61,754	65,825
Goodwill, net	2,381,309	2,396,096
Other intangible assets, net	364,425	378,818
Capitalized data and database costs, net	320,226	327,078
Investment in affiliates, net	11,339	16,666
Other assets	71,753	76,604
Total assets	4,147,607	4,158,657
Current liabilities:
Accounts payable and other accrued expenses	174,007	173,989
Accrued salaries and benefits	66,643	86,598
Contract liabilities, current	341,068	321,647
Current portion of long-term debt	77,724	56,022
Operating lease liabilities, current	17,532	18,058
Total current liabilities	676,974	656,314
Long-term debt, net of current	1,589,507	1,610,538
Contract liabilities, net of current	568,964	563,246
Deferred income tax liabilities	85,008	110,396
Operating lease liabilities, net of current	80,301	85,139
Other liabilities	219,855	181,814
Total liabilities	3,220,609	3,207,447
Stockholders' equity:
Preferred stock, $0.00001 par value; 500 shares authorized, no shares issued or outstanding	0	0
Common stock, $0.00001 par value; 180,000 shares authorized; 79,411 and 78,972 shares issued and outstanding as of March 31, 2020 and December 31, 2019, respectively	1	1
Additional paid-in capital	111,481	111,000
Retained earnings	1,057,692	1,006,992
Accumulated other comprehensive loss	(242,176)	(166,783)
Total stockholders' equity	926,998	951,210
Total liabilities and equity	$ 4,147,607	$ 4,158,657