Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets
Cash and cash equivalents	$ 132,914	$ 82,407
Accounts receivable, net of allowance of $5,057 and $5,452, respectively	378,397	331,096
Prepaids and other current assets	104,597	96,287
Income and other tax receivables	40,894	40,035
Total current assets	656,802	549,825
Long-term assets
Property, plant and equipment, net	178,706	176,633
Operating lease assets	120,820	150,808
Goodwill	363,502	301,694
Deferred tax assets, net	15,081	13,263
Other intangible assets, net	112,059	115,596
Other long-term assets	69,438	68,969
Total long-term assets	859,606	826,963
Total assets	1,516,408	1,376,788
Current liabilities
Accounts payable	66,658	64,440
Accrued employee compensation and benefits	163,658	114,165
Other accrued expenses	55,915	79,171
Income taxes payable	19,709	11,307
Deferred revenue	39,956	39,447
Current operating lease liabilities	43,651	45,218
Other current liabilities	6,623	9,541
Total current liabilities	396,170	363,289
Long-term liabilities
Line of credit	385,000	290,000
Deferred tax liabilities, net	7,747	10,602
Non-current Income Taxes Payable	22,291	25,208
Non-current operating lease liabilities	98,277	127,395
Other long-term liabilities	96,185	79,641
Total long-term liabilities	609,500	532,846
Total liabilities	1,005,670	896,135
Redeemable noncontrolling interest	52,976	48,923
Stockholders' equity
Common stock - $0.01 par value; 150,000,000 shares authorized; 46,737,033 and 46,488,938 shares outstanding as of December 31, 2020 and December 31, 2019, respectively	467	465
Additional paid-in capital	360,293	356,409
Treasury stock at cost: 35,315,220 and 35,563,315 shares as of December 31, 2020 and December 31, 2019, respectively	(601,214)	(605,314)
Accumulated other comprehensive income (loss)	(72,156)	(106,234)
Retained earnings	757,312	773,218
Noncontrolling interest	13,060	13,186
Total stockholders' equity	457,762	431,730
Total liabilities and stockholders' equity	$ 1,516,408	$ 1,376,788