Segment Information - Segment Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Net service revenue	$ 260,210	$ 226,031	$ 506,828	$ 448,583
Cost of service revenue	161,158	137,128	315,528	272,729
Provision for bad debts	2,675	3,782	5,044	8,383
General and administrative expenses	73,550	68,261	145,409	134,297
Loss on disposal of assets	2	1,043	154	1,247
Operating income	22,825	15,817	40,693	31,927
Interest expense	(840)	(466)	(1,620)	(1,351)
Income before income taxes and noncontrolling interest	21,985	15,351	39,073	30,576
Income tax expense	7,792	3,596	12,965	8,938
Net income	14,193	11,755	26,108	21,638
Less net income attributable to noncontrolling interests	2,889	2,291	5,337	4,488
Net income attributable to LHC Group, Inc.’s common stockholders	11,304	9,464	20,771	17,150
Total assets	672,666	619,645	672,666	619,645	$ 614,071
Home health services
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Net service revenue	194,061	163,174	376,202	324,561
Cost of service revenue	117,606	97,590	229,692	194,302
Provision for bad debts	1,652	2,618	3,135	6,073
General and administrative expenses	55,267	51,182	109,171	100,655
Loss on disposal of assets	1	706	19	791
Operating income	19,535	11,078	34,185	22,740
Interest expense	(630)	(350)	(1,215)	(1,028)
Income before income taxes and noncontrolling interest	18,905	10,728	32,970	21,712
Income tax expense	6,757	2,043	11,010	5,893
Net income	12,148	8,685	21,960	15,819
Less net income attributable to noncontrolling interests	2,266	1,555	4,294	3,149
Net income attributable to LHC Group, Inc.’s common stockholders	9,882	7,130	17,666	12,670
Total assets	466,308	429,780	466,308	429,780
Community-based services
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Net service revenue	10,845	10,587	21,661	21,030
Cost of service revenue	7,986	7,829	15,934	15,556
Provision for bad debts	99	216	374	298
General and administrative expenses	2,261	2,215	4,572	4,294
Loss on disposal of assets	0	46	0	46
Operating income	499	281	781	836
Interest expense	(42)	(23)	(81)	(65)
Income before income taxes and noncontrolling interest	457	258	700	771
Income tax expense	180	102	263	330
Net income	277	156	437	441
Less net income attributable to noncontrolling interests	5	(14)	13	(57)
Net income attributable to LHC Group, Inc.’s common stockholders	272	170	424	498
Total assets	33,292	33,247	33,292	33,247
Hospice Services
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Net service revenue	38,513	33,905	74,958	64,729
Cost of service revenue	24,473	20,966	47,746	40,593
Provision for bad debts	662	792	1,159	1,567
General and administrative expenses	10,742	9,425	21,141	18,296
Loss on disposal of assets	1	205	8	324
Operating income	2,635	2,517	4,904	3,949
Interest expense	(126)	(51)	(243)	(142)
Income before income taxes and noncontrolling interest	2,509	2,466	4,661	3,807
Income tax expense	849	789	1,508	1,209
Net income	1,660	1,677	3,153	2,598
Less net income attributable to noncontrolling interests	480	498	766	815
Net income attributable to LHC Group, Inc.’s common stockholders	1,180	1,179	2,387	1,783
Total assets	138,519	118,353	138,519	118,353
Facility-based services
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Net service revenue	16,791	18,365	34,007	38,263
Cost of service revenue	11,093	10,743	22,156	22,278
Provision for bad debts	262	156	376	445
General and administrative expenses	5,280	5,439	10,525	11,052
Loss on disposal of assets	0	86	127	86
Operating income	156	1,941	823	4,402
Interest expense	(42)	(42)	(81)	(116)
Income before income taxes and noncontrolling interest	114	1,899	742	4,286
Income tax expense	6	662	184	1,506
Net income	108	1,237	558	2,780
Less net income attributable to noncontrolling interests	138	252	264	581
Net income attributable to LHC Group, Inc.’s common stockholders	(30)	985	294	2,199
Total assets	$ 34,547	$ 38,265	$ 34,547	$ 38,265