Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
ASSETS
Cash and cash equivalents	$ 616,820	$ 575,615
Accounts receivable, net of allowances of $11,834 and $12,701, respectively	188,383	261,928
Prepaid expenses and other current assets	45,767	49,347
Total current assets	853,145	886,890
Long-term investments	94,042	100,079
Property and equipment, net	144,494	127,817
Operating Lease, Right-of-Use Asset	110,031	125,822
Trade names, net	130,540	138,029
Customer relationships, net	206,478	238,502
Goodwill	1,637,287	1,633,033
Other purchased intangibles, net	153,417	180,022
Deferred Income Tax Assets, Net	56,947	59,976
Other assets	16,199	15,676
Total assets	3,419,445	3,505,846
LIABILITIES AND STOCKHOLDERS’ EQUITY
Accounts payable and accrued expenses	166,289	238,059
Income taxes payable, current	24,402	17,758
Deferred revenue, current	159,907	162,855
Operating Lease, Liability, Current	26,602	26,927
Current maturities of long-term debt	391,092	385,532
Other current liabilities	1,501	1,973
Total current liabilities	772,181	833,104
Long-term debt	1,071,364	1,062,929
Deferred revenue, noncurrent	11,501	12,744
Operating Lease, Liability, Noncurrent	91,279	104,070
Accrued Income Taxes, Noncurrent	11,675	11,675
Liability for uncertain tax positions	57,565	52,451
Deferred Income Tax Liabilities, Net	111,746	107,453
Other long-term liabilities	28,810	10,228
Total liabilities	2,156,277	2,194,654
Commitments and contingencies	0	0
Preferred stock, $0.01 par value	0	0
Common stock, $0.01 par value. Authorized 95,000,000; total issued and outstanding 46,892,691 and 47,654,929 shares at June 30, 2020 and December 31, 2019, respectively.	469	476
Additional paid-in capital	467,267	465,652
Retained earnings	850,232	891,526
Accumulated other comprehensive loss	(54,800)	(46,462)
Stockholders' Equity Attributable to Parent	1,263,168	1,311,192
Total liabilities and stockholders’ equity	$ 3,419,445	$ 3,505,846
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	95,000,000	95,000,000
Common stock, shares issued	46,892,691	47,654,929
Common stock, shares outstanding	46,892,691	47,654,929
Allowance for doubtful accounts	$ 11,834	$ 12,701
Disposal Group, Held-for-sale, Not Discontinued Operations
ASSETS
Disposal Group, Including Discontinued Operation, Assets, Current	2,175	0
Disposal Group, Including Discontinued Operation, Assets, Noncurrent	16,865	0
LIABILITIES AND STOCKHOLDERS’ EQUITY
Disposal Group, Including Discontinued Operation, Liabilities, Current	2,388	0
Disposal Group, Including Discontinued Operation, Liabilities, Noncurrent	156	0
Series A Preferred Stock [Member]
LIABILITIES AND STOCKHOLDERS’ EQUITY
Preferred stock, $0.01 par value	$ 0	$ 0
Preferred stock, shares authorized	6,000	6,000
Series B Preferred Stock [Member]
LIABILITIES AND STOCKHOLDERS’ EQUITY
Preferred stock, $0.01 par value	$ 0	$ 0
Preferred stock, shares authorized	20,000	20,000