Accounting Policies - Additional Information (Detail) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
	Nov. 30, 2017	Dec. 31, 2020 USD ($) Claim State Surgery_Center Endoscopy_Center Hospital	Dec. 31, 2020 USD ($) Claim State Surgery_Center Endoscopy_Center Hospital	Dec. 31, 2019 USD ($) Claim	Dec. 31, 2018 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of owned and operated hospitals | Hospital		185	185
Number of freestanding surgery centers | Surgery_Center		121	121
Number of freestanding endoscopy centers | Endoscopy_Center		21	21
Number of facilities locations | State		20	20
General and administrative expense			$ 416,000	$ 370,000	$ 344,000
Adjustments to estimated reimbursement filed during respective year			70,000	51,000	29,000
Adjustments to estimated reimbursement filed during previous years			(5,000)	13,000	51,000
Estimated implicit price concessions recorded as reductions to revenues and accounts receivable			6,108,000	6,953,000
Charity care amount			13,763,000	13,260,000	8,611,000
Estimated costs of charity care			1,652	1,591	$ 1,068,000
Outstanding checks unpresented for payment		$ 495,000	$ 495,000	$ 486,000
Days revenues in accounts receivable			45 days	50 days	51 days
Depreciation expense			$ 2,693,000	$ 2,579,000	$ 2,262,000
Goodwill impairments			0	0	0
Goodwill acquired during period			279,000	332,000
Intangible assets decreased			26,000	12,000
Gross carrying amount of intangible assets			249,000	184,000
Accumulated amortization of intangible assets		149,000	149,000	123,000
Gross carrying amount of indefinite-lived intangible assets		269,000	269,000	269,000
Deferred loan costs		411,000	411,000	413,000
Deferred loan costs, accumulated amortization		175,000	175,000	174,000
Amortization of debt issuance costs			30,000	30,000	31,000
Reserves for professional liability risks		1,963,000	1,963,000	1,827,000
Current portion of professional liability risks reserves		$ 477,000	477,000	457,000
Provisions for losses related to professional liability risks			435,000	497,000	447,000
Decrease in provision for professional liability risks			$ 112,000	$ 50,000	70,000
Reserves for professional liability risks cover individual claims | Claim		2,300	2,300	2,300
Net payments of professional and general liability claims			$ 292,000	$ 408,000
Self-insured retention amount per occurrence					15,000
Maximum amount losses per occurrence					$ 50,000
Reinsurance for professional liability risks retention minimum level of amount per occurrence			25,000
Reinsurance for professional liability risks retention level of amount per occurrence			35,000
Amounts receivable under reinsurance contracts recorded in other assets		$ 31,000	31,000	37,000
Amounts receivable under reinsurance contracts recorded in other current assets		8,000	8,000	9,000
Government stimulus refund liability		83,000	83,000
Increase decrease in accounts receivable			$ 329,000
Percentage increase in fourth quarter revenues per day			5.70%
CARES Act Provider Relief Fund [Member]
Summary Of Significant Accounting Policies [Line Items]
Accelerated Medicare payments received			$ 4,400,000
General and targeted distributions recived			1,800,000
Deferred social security taxes		688,000	688,000
Employee retention payroll tax credits			60,000
Repayments of provider relief funds		6,100,000
Government stimulus refund liability		$ 83,000	83,000
Foreign Currency Translation And Other [Member]
Summary Of Significant Accounting Policies [Line Items]
Goodwill increase (decrease)			$ 9,000	$ 4,000
Insurance Subsidiary [Member]
Summary Of Significant Accounting Policies [Line Items]
Insurance subsidiary ownership percentage				100.00%
Inpatient Services [Member]
Summary Of Significant Accounting Policies [Line Items]
Performance obligations for inpatient/ outpatient services satisfied period			Our performance obligations for inpatient services are generally satisfied over periods that average approximately five days
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of income of federal poverty level eligible for charity care	400.00%
Finite lived intangible asset useful life			10 years
Maximum [Member] | Outpatient Services [Member]
Summary Of Significant Accounting Policies [Line Items]
Performance obligations for inpatient/ outpatient services satisfied period			Our performance obligations for outpatient services are generally satisfied over a period of less than one day
Maximum [Member] | Building and Improvements [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives in years			40 years
Maximum [Member] | Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives in years			10 years
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Finite lived intangible asset useful life			3 years
Minimum [Member] | Building and Improvements [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives in years			10 years
Minimum [Member] | Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives in years			4 years