Segment Information - Summary of segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Net service revenue	$ 502,585	$ 291,054
Cost of service revenue	320,992	188,618
General and administrative expenses	145,221	92,031
Other intangible impairment charge	6,319	0
Operating income	30,053	10,405
Interest expense	(3,052)	(1,450)
Income before income taxes and noncontrolling interest	27,001	8,955
Income tax expense	3,600	977
Net income	23,401	7,978
Less net income (loss) attributable to noncontrolling interests	4,545	2,983
Net income attributable to LHC Group, Inc.’s common stockholders	18,856	4,995
Total assets	2,013,857	805,323	$ 1,928,715
Home health services
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Net service revenue	363,035	204,187
Cost of service revenue	226,123	130,161
General and administrative expenses	104,839	66,289
Other intangible impairment charge	6,318
Operating income	25,755	7,737
Interest expense	(2,138)	(1,088)
Income before income taxes and noncontrolling interest	23,617	6,649
Income tax expense	3,208	722
Net income	20,409	5,927
Less net income (loss) attributable to noncontrolling interests	3,780	2,236
Net income attributable to LHC Group, Inc.’s common stockholders	16,629	3,691
Total assets	1,421,000	530,197
Hospice services
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Net service revenue	51,736	42,626
Cost of service revenue	33,176	28,018
General and administrative expenses	14,853	13,298
Other intangible impairment charge	1
Operating income	3,706	1,310
Interest expense	(343)	(218)
Income before income taxes and noncontrolling interest	3,363	1,092
Income tax expense	446	111
Net income	2,917	981
Less net income (loss) attributable to noncontrolling interests	601	417
Net income attributable to LHC Group, Inc.’s common stockholders	2,316	564
Total assets	220,347	157,338
Home and community-based services
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Net service revenue	51,785	14,091
Cost of service revenue	39,855	10,790
General and administrative expenses	10,982	3,298
Other intangible impairment charge	0
Operating income	948	3
Interest expense	(301)	(72)
Income before income taxes and noncontrolling interest	647	(69)
Income tax expense	151	(15)
Net income	496	(54)
Less net income (loss) attributable to noncontrolling interests	(310)	21
Net income attributable to LHC Group, Inc.’s common stockholders	806	(75)
Total assets	226,991	47,819
Facility-based services
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Net service revenue	27,701	30,150
Cost of service revenue	17,732	19,649
General and administrative expenses	9,177	9,146
Other intangible impairment charge	0
Operating income	792	1,355
Interest expense	(180)	(72)
Income before income taxes and noncontrolling interest	612	1,283
Income tax expense	5	159
Net income	607	1,124
Less net income (loss) attributable to noncontrolling interests	481	309
Net income attributable to LHC Group, Inc.’s common stockholders	126	815
Total assets	79,257	69,969
HCI
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Net service revenue	8,328	0
Cost of service revenue	4,106	0
General and administrative expenses	5,370	0
Other intangible impairment charge	0
Operating income	(1,148)	0
Interest expense	(90)	0
Income before income taxes and noncontrolling interest	(1,238)	0
Income tax expense	(210)	0
Net income	(1,028)	0
Less net income (loss) attributable to noncontrolling interests	(7)	0
Net income attributable to LHC Group, Inc.’s common stockholders	(1,021)	0
Total assets	$ 66,262	$ 0