UNAUDITED SUMMARIZED QUARTERLY FINANCIAL INFORMATION Operating Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Net service revenue	$ 550,700	$ 544,100	$ 485,000	$ 491,700	$ 500,700	$ 494,600	$ 493,000	$ 467,300	$ 2,071,519	$ 1,955,633	$ 1,662,578
Net income attributable to Amedisys, Inc.	$ 45,100	$ 72,000	$ 34,700	$ 31,800	$ 27,700	$ 34,100	$ 33,700	$ 31,300	$ 183,608	$ 126,833	$ 119,346
Net income attributable to Amedisys, Inc. common stockholders - basic (usd per share)	$ 1.38	$ 2.20	$ 1.07	$ 0.98	$ 0.86	$ 1.06	$ 1.05	$ 0.98	$ 5.64	$ 3.95	$ 3.64
Net income attributable to Amedisys, Inc. common stockholders - diluted (usd per share)	$ 1.36	$ 2.16	$ 1.04	$ 0.96	$ 0.83	$ 1.03	$ 1.02	$ 0.95	$ 5.52	$ 3.84	$ 3.55