CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
CURRENT ASSETS:
Cash and cash equivalents	$ 119,423	$ 99,265
Accounts receivable, net	338,242	328,340
Inventories	183,095	158,601
Prepaid expenses and other current assets	69,496	70,806
Total current assets	710,256	657,012
NONCURRENT ASSETS:
Property and equipment, net	111,535	121,149
Operating lease right-of-use asset	74,777	68,795
Intangible assets, net	21,433	23,429
Referral sources	344,587	327,623
Goodwill	1,477,564	1,428,610
Deferred income taxes	27,033	0
Other noncurrent assets	23,733	20,821
Total noncurrent assets	2,080,662	1,990,427
TOTAL ASSETS	2,790,918	2,647,439
CURRENT LIABILITIES:
Accounts payable	279,246	282,913
Accrued compensation and employee benefits	83,503	58,899
Accrued expenses and other current liabilities	71,857	64,075
Current portion of operating lease liability	19,089	18,886
Current portion of long-term debt	6,000	9,250
Total current liabilities	459,695	434,023
NONCURRENT LIABILITIES:
Long-term debt, net of discount, deferred financing costs and current portion	1,059,900	1,115,103
Operating lease liability, net of current portion	74,492	70,776
Deferred income taxes	0	3,339
Other noncurrent liabilities	20,945	8,474
Total noncurrent liabilities	1,155,337	1,197,692
Total liabilities	1,615,032	1,631,715
STOCKHOLDERS’ EQUITY:
Preferred stock; $0.0001 par value; 12,500,000 shares authorized, no shares outstanding as of December 31, 2021 and 2020, respectively.	0	0
Common stock; $0.0001 par value: 250,000,000 shares authorized, 180,309,637 shares issued and 179,925,915 shares outstanding as of December 31, 2021; 180,178,308 shares issued and 179,794,586 shares outstanding as of December 31, 2020.	18	18
Treasury stock; 383,722 shares outstanding, at cost, as of December 31, 2021 and 2020, respectively.	(2,403)	(2,403)
Paid-in capital	1,138,855	1,129,312
Retained earnings (Accumulated deficit)	39,867	(100,031)
Accumulated other comprehensive loss	(451)	(11,172)
Total stockholders’ equity	1,175,886	1,015,724
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 2,790,918	$ 2,647,439