Chesapeake Utilities (CPK) 10-Q 3 Nov 21 2021 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2021	Jul. 31, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Document Transition Report	false
Entity File Number	001-11590
Entity Registrant Name	CHESAPEAKE UTILITIES CORP
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	51-0064146
Entity Address, Address Line One	909 Silver Lake Boulevard
Entity Address, City or Town	Dover
Entity Address, State or Province	DE
Entity Address, Postal Zip Code	19904
City Area Code	302
Local Phone Number	734-6799
Title of 12(b) Security	Common Stock - par value per share $0.4867
Trading Symbol	CPK
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		17,604,196
Entity Central Index Key	0000019745
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Operating Revenues
Regulated Energy	$ 80,396	$ 82,762	$ 282,503	$ 259,235
Unregulated Energy and other	26,939	18,657	127,101	91,925
Total Operating Revenues	107,335	101,419	409,604	351,160
Operating Expenses
Regulated Energy cost of sales	15,294	16,271	72,785	67,490
Unregulated Energy and other cost of sales	12,072	5,640	55,578	30,250
Operations	34,075	34,959	109,886	105,516
Maintenance	4,267	3,717	12,568	11,695
Settlement Gain			0	(130)
Depreciation and amortization	15,798	18,293	46,460	42,793
Other taxes	5,716	5,133	18,039	16,028
Total Operating Expenses	87,222	84,013	315,316	273,642
Total operating income	20,113	17,406	94,288	77,518
Other income (expense), net	339	(40)	2,180	2,997
Interest charges	4,975	4,584	15,134	15,452
Income from Continuing Operations Before Income Taxes	15,477	12,782	81,334	65,063
Income Taxes on Continuing Operations	2,993	3,502	20,563	16,082
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent	12,484	9,280	60,771	48,981
Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, Net of Tax	(9)	(19)	(17)	165
Net Income	$ 12,475	$ 9,261	$ 60,754	$ 49,146
Weighted Average Common Shares Outstanding:
Basic (shares)	17,582,115	16,533,748	17,538,461	16,466,106
Diluted (shares)	17,659,643	16,592,842	17,610,158	16,523,200
Basic Earnings Per Share of Common Stock:
Income (Loss) from Continuing Operations, Per Basic Share	$ 0.71	$ 0.56	$ 3.46	$ 2.97
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share	0	0	0	0.01
Basic (in dollars per share)	0.71	0.56	3.46	2.98
Earnings Per Share, Diluted [Abstract]
Income (Loss) from Continuing Operations, Per Diluted Share	0.71	0.56	3.45	2.96
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share	0	0	0	0.01
Diluted (in dollars per share)	$ 0.71	$ 0.56	$ 3.45	$ 2.97

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net Income	$ 12,475	$ 9,261	$ 60,754	$ 49,146
Amortization of prior service cost, net of tax of $(5), $(5), $(15) and $(15), respectively	(14)	(14)	(42)	(42)
Net gain, net of tax of $28, $28, $53 and $55, respectively	(78)	(80)	(234)	(240)
Unrealized gain on commodity contract cash flow hedges, net of tax of $688, $282, $1,945 and $935, respectively	1,803	740	5,094	2,450
Unrealized gain/(loss) on interest rate swap cash flow hedges, net of tax of $2, $(14), $1 and $(14), respectively	14	27	18	(10)
Other comprehensive income (loss)	1,881	833	5,304	2,638
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 14,356	$ 10,094	$ 66,058	$ 51,784

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Other Comprehensive Income [Abstract]
Amortization of prior service cost, tax	$ (5)	$ (5)	$ (15)	$ (15)
Net gain, tax	28	28	83	83
Unrealized (loss)/gain on commodity contract cash flow hedges, tax	688	282	1,945	935
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Interest Rate Swaps During Period, Tax	$ 5	$ 10	$ 6	$ (4)

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2021		Dec. 31, 2020
Property, Plant and Equipment
Regulated Energy	$ 1,688,938		$ 1,577,576
Unregulated Energy	324,083		300,647
Other businesses and eliminations	35,183		30,769
Total property, plant and equipment	2,048,204		1,908,992
Less: Accumulated depreciation and amortization	(405,263)		(368,743)
Plus: Construction work in progress	56,773		60,929
Net property, plant and equipment	1,699,714		1,601,178
Current Assets
Cash and cash equivalents	5,886		3,499
Trade and other receivables	44,590		56,890
Accounts Receivable, Allowance for Credit Loss, Current	(2,980)		(4,785)
Accounts Receivable, before Allowance for Credit Loss, Current	47,570		61,675
Accrued revenue	11,318		21,527
Propane inventory, at average cost	6,917		5,906
Other inventory, at average cost	6,716		5,539
Regulatory assets	12,021		10,786
Storage gas prepayments	4,663		2,455
Income taxes receivable	12,702		12,885
Prepaid expenses	15,555		13,239
Derivative assets, at fair value	12,185		3,269
Other current assets	440		436
Total current assets	132,993		136,431
Deferred Charges and Other Assets
Goodwill	38,803		38,731
Other intangible assets, net	7,298		8,292
Investments, at fair value	11,490		10,776
Operating Lease, Right-of-Use Asset	9,602		11,194
Regulatory assets	107,872		113,806
Receivables and other deferred charges	14,056		12,079
Total deferred charges and other assets	189,121		194,878
Total Assets	2,021,828		1,932,487
Stockholders’ equity
Preferred stock, par value $0.01 per share (authorized 2,000,000 shares), no shares issued and outstanding	0		0
Common stock, par value $0.4867 per share (authorized 50,000,000 shares)	8,560		8,499
Additional paid-in capital	361,066		348,482
Retained earnings	378,897		342,969
Accumulated other comprehensive income (loss)	2,439		(2,865)
Deferred compensation obligation	7,186		5,679
Treasury stock	(7,186)		(5,679)
Total stockholders’ equity	750,962	[1]	697,085
Long-term debt, net of current maturities	505,459		508,499
Total capitalization	1,256,421		1,205,584
Current Liabilities
Less: current maturities	16,206		13,600
Short-term borrowing	192,026		175,644
Accounts payable	53,026		60,253
Customer deposits and refunds	35,782		33,302
Accrued interest	4,783		2,905
Dividends payable	8,442		7,683
Accrued compensation	13,497		13,994
Regulatory liabilities	5,357		6,284
Derivative liabilities, at fair value	1,969		127
Other accrued liabilities	23,454		15,240
Total current liabilities	354,542		329,032
Deferred Credits and Other Liabilities
Deferred income taxes	225,448		205,388
Regulatory liabilities	143,164		142,736
Environmental liabilities	3,709		4,299
Other pension and benefit costs	28,113		30,673
Operating Lease, Liability, Noncurrent	8,380		9,872
Deferred investment tax credits and other liabilities	2,051		4,903
Total deferred credits and other liabilities	410,865		397,871
Environmental and other commitments and contingencies (Notes 5 and 6)
Total Capitalization and Liabilities	$ 2,021,828		$ 1,932,487
[1]	2,000,000 shares of preferred stock at $0.01 par value have been authorized. No shares have been issued or are outstanding; accordingly, no information has been included in the statements of stockholders’ equity.

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Allowance for uncollectible accounts	$ 2,980	$ 4,785
Common stock, par value (in dollars per share)	$ 0.4867	$ 0.4867
Common stock, shares authorized (shares)	50,000,000	50,000,000
Preferred Stock, Shares Authorized	2,000,000	2,000,000
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Shares Issued	0	0

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Operating Activities
Net Income	$ 60,754	$ 49,146
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	46,460	42,793
Depreciation and accretion included in other costs	7,668	7,062
Deferred income taxes	18,059	22,184
Gain on sale of discontinued operations	0	(200)
Realized gain on commodity contracts and sale of assets	(6,255)	(4,876)
Unrealized (gain) loss on investments/commodity contracts	(949)	(432)
Employee benefits and compensation	(519)	32
Share-based compensation	4,620	3,654
Changes in assets and liabilities:
Accounts receivable and accrued revenue	22,439	10,255
Propane inventory, storage gas and other inventory	(4,396)	2,824
Regulatory assets/liabilities, net	(6,562)	(2,284)
Prepaid expenses and other current assets	(6,813)	1,135
Accounts payable and other accrued liabilities	18,325	(924)
Income taxes (payable) receivable	183	(6,809)
Customer deposits and refunds	2,480	1,572
Accrued compensation	(740)	(5,506)
Other assets and liabilities, net	(1,970)	(3,746)
Net cash provided by operating activities	152,784	115,880
Investing Activities
Property, plant and equipment expenditures	(148,213)	(123,421)
Proceeds from sale of assets	727	4,320
Proceeds from the sale of discontinued operations	0	200
Environmental expenditures	590	2,021
Net cash used in investing activities	(148,076)	(136,551)
Financing Activities
Common stock dividends	(23,287)	(20,044)
Issuance of stock under the Dividend Reinvestment Plan, net of offering fees	7,069	19,731
Tax withholding payments related to net settled stock compensation	(1,478)	(977)
Change in cash overdrafts due to outstanding checks	(508)	(2,310)
Net advances (repayments) under line of credit agreements	16,392	(29,385)
Proceeds from long-term debt, net of offering fees	9,590	89,827
Repayment of long-term debt	(10,099)	(40,100)
Net cash (used in) / provided by financing activities	(2,321)	16,742
Net Increase (Decrease) in Cash and Cash Equivalents	2,387	(3,929)
Cash and Cash Equivalents—Beginning of Period	3,499	6,985
Cash and Cash Equivalents—End of Period	5,886	3,056
Payments to Acquire Businesses, Gross	$ 0	$ (15,629)

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands		Total		Common Stock [Member]		Additional Paid-In Capital [Member]		Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Deferred Compensation [Member]	Treasury Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares Held In Trust For Deferred Compensation Plan		95,329
Common Stock, Dividends, Per Share, Declared		$ 1.285
Beginning Balances (shares) at Dec. 31, 2019	[1],[2]			16,403,776
Beginning Balances at Dec. 31, 2019		$ 561,577	[1],[2]	$ 7,984	[1],[2]	$ 259,253		$ 300,607	$ (6,267)	$ 4,543	$ (4,543)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		49,146						49,146
Other comprehensive income (loss)		2,638							2,638
Other Comprehensive Income (Loss), Net of Tax		2,638
Dividend declared		(21,366)						(21,366)
Retirement savings plan and dividend reinvestment plan (shares)				258,260
Dividend reinvestment plan		21,819		$ 126		21,693
Share-based compensation (shares)	[3],[4]			34,456
Share-based compensation and tax benefit		2,906		$ 16	[3],[4]	2,890	[3],[4]
Treasury stock activities		0								1,091	(1,091)
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, QuantificationPrincipleEffectOfAdoptionQuantification		(30)						(30)
Ending Balances (shares) at Sep. 30, 2020	[1],[2]			16,696,492
Ending Balances at Sep. 30, 2020		$ 616,690	[1]	$ 8,126	[1]	283,836		328,357	(3,629)	5,634	(5,634)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation		10,319
Common Stock, Dividends, Per Share, Declared		$ 0.4400
Beginning Balances (shares) at Jun. 30, 2020	[1],[2]			16,463,808
Beginning Balances at Jun. 30, 2020		$ 593,277	[1]	$ 8,013	[1]	263,272		326,454	(4,462)	5,659	(5,659)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		9,261						9,261
Other comprehensive income (loss)		833							833
Other Comprehensive Income (Loss), Net of Tax		833
Dividend declared		(7,358)						(7,358)
Retirement savings plan and dividend reinvestment plan (shares)				232,684
Dividend reinvestment plan		19,533		$ 113		19,420
Share-based compensation (shares)	[3],[4]			0
Share-based compensation and tax benefit	[3],[4]	1,144		$ 0		1,144
Treasury stock activities										(25)	25
Ending Balances (shares) at Sep. 30, 2020	[1],[2]			16,696,492
Ending Balances at Sep. 30, 2020		$ 616,690	[1]	$ 8,126	[1]	283,836		328,357	(3,629)	5,634	(5,634)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares Held In Trust For Deferred Compensation Plan		104,119
Preferred Stock, Shares Authorized		2,000,000
Preferred Stock, Par or Stated Value Per Share		$ 0.01
Shares Held In Trust For Deferred Compensation Plan		105,087
Common Stock, Dividends, Per Share, Declared		$ 1.400
Beginning Balances (shares) at Dec. 31, 2020	[1],[2]			17,461,841
Beginning Balances at Dec. 31, 2020		$ 697,085		$ 8,499	[1],[2]	348,482		342,969	(2,865)	5,679	(5,679)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		60,754						60,754
Other comprehensive income (loss)		5,304							5,304
Other Comprehensive Income (Loss), Net of Tax		5,304
Dividend declared		(24,826)						(24,826)
Retirement savings plan and dividend reinvestment plan (shares)				80,022
Dividend reinvestment plan		9,286		$ 39		9,247
Share-based compensation (shares)	[3],[4]			45,971
Share-based compensation and tax benefit	[3],[4]	3,359		$ 22		3,337
Treasury stock activities								0		1,507	(1,507)
Ending Balances (shares) at Sep. 30, 2021	[1],[2]			17,587,834
Ending Balances at Sep. 30, 2021		$ 750,962	[1]	$ 8,560	[1]	361,066		378,897	2,439	7,186	(7,186)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation		14,020
Common Stock, Dividends, Per Share, Declared		$ 0.4800
Beginning Balances (shares) at Jun. 30, 2021	[1],[2]			17,567,928
Beginning Balances at Jun. 30, 2021		$ 741,564	[1]	$ 8,550	[1]	357,520		374,936	558	7,203	(7,203)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		12,475						12,475
Other comprehensive income (loss)		1,881							1,881
Other Comprehensive Income (Loss), Net of Tax		1,881
Dividend declared		(8,514)						(8,514)
Retirement savings plan and dividend reinvestment plan (shares)				19,906
Dividend reinvestment plan		2,451		$ 10		2,441
Share-based compensation (shares)	[3],[4]			0
Share-based compensation and tax benefit	[3],[4]	1,105		$ 0		1,105
Treasury stock activities		0								(17)	17
Ending Balances (shares) at Sep. 30, 2021	[1],[2]			17,587,834
Ending Balances at Sep. 30, 2021		$ 750,962	[1]	$ 8,560	[1]	$ 361,066		$ 378,897	$ 2,439	$ 7,186	$ (7,186)
Preferred Stock, Shares Authorized		2,000,000
Preferred Stock, Par or Stated Value Per Share		$ 0.01
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares Held In Trust For Deferred Compensation Plan		114,016
[1]	2,000,000 shares of preferred stock at $0.01 par value have been authorized. No shares have been issued or are outstanding; accordingly, no information has been included in the statements of stockholders’ equity.
[2]	Includes 114,016, 105,087, 104,119, and 95,329 shares at September 30, 2021, December 31, 2020, September 30, 2020 and December 31, 2019, respectively, held in a Rabbi Trust related to our Non-Qualified Deferred Compensation Plan.
[3]	Includes amounts for shares issued for directors’ compensation.
[4]	The shares issued under the SICP are net of shares withheld for employee taxes. For the nine months ended September 30, 2021 and 2020, we withheld 14,020 and 10,319 shares, respectively, for employee taxes.

Condensed Consolidated Statem_6

Condensed Consolidated Statements of Stockholders' Equity (Parenthetical) (Unaudited) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Statement of Stockholders' Equity [Abstract]
Dividend declared (in dollars per share)	$ 0.4800	$ 0.4400	$ 1.400	$ 1.285
Deferred compensation plan held Rabbi Trust (shares)	114,016	104,119	114,016	104,119	105,087	95,329
Preferred Stock, Shares Authorized	2,000,000		2,000,000		2,000,000
Preferred Stock, Par or Stated Value Per Share	$ 0.01		$ 0.01		$ 0.01
Shares issued under the performance incentive plan withheld for employee taxes (shares)			14,020	10,319

Summary of Accounting Policies

Summary of Accounting Policies	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Summary of Accounting Policies	Summary of Accounting Policies Basis of Presentation References in this document to the “Company,” “Chesapeake Utilities,” “we,” “us” and “our” are intended to mean Chesapeake Utilities Corporation, its divisions and/or its subsidiaries, as appropriate in the context of the disclosure. The accompanying unaudited condensed consolidated financial statements have been prepared in compliance with the rules and regulations of the SEC and GAAP. In accordance with these rules and regulations, certain information and disclosures normally required for audited financial statements have been condensed or omitted. These financial statements should be read in conjunction with the consolidated financial statements and notes thereto, included in our latest Annual Report on Form 10-K for the year ended December 31, 2020. In the opinion of management, these financial statements reflect all adjustments that are necessary for a fair presentation of our results of operations, financial position and cash flows for the interim periods presented. Where necessary to improve comparability, prior period amounts have been changed to conform to current period presentation. Due to the seasonality of our business, results for interim periods are not necessarily indicative of results for the entire fiscal year. Revenue and earnings are typically greater during the first and fourth quarters, when consumption of energy is highest due to colder temperatures. Effects of COVID-19 In March 2020, the CDC declared a national emergency due to the rapidly growing outbreak of COVID-19. In response to this declaration and the rapid spread of COVID-19 within the United States, federal, state and local governments throughout the country imposed varying degrees of restrictions on social and commercial activity to promote social distancing in an effort to slow the spread of the illness. These restrictions significantly impacted economic conditions in the United States in 2020 and continued into 2021. Chesapeake Utilities is considered an “essential business,” which has allowed us to continue operational activities and construction projects while adhering to the social distancing restrictions that were in place. At this time, restrictions continue to be lifted as vaccines have become widely available in the United States. For example, the state of emergency in Florida was terminated in May 2021 followed by Delaware and Maryland in July 2021, resulting in reduced restrictions. The expiration of the states of emergency in our service territories has concluded our ability to defer incremental pandemic related costs for consideration through the applicable regulatory process. Despite these positive state orders and in light of the continued emergence and growing prevalence of the new variants of COVID-19, we continue to operate under our pandemic response plan, monitor developments affecting employees, customers, suppliers, and stockholders and take all precautions warranted to operate safely and to comply with the CDC, Occupational Safety and Health Administration, in order to protect our employees, customers and the communities we serve. Refer to Note 5 , Rates and Other Regulatory Activities , for further information on the regulated assets established as a result of the incremental expenses incurred associated with COVID-19. FASB Statements and Other Authoritative Pronouncements There are no new accounting pronouncements issued that are applicable to us.

Calculation of Earnings Per Sha

Calculation of Earnings Per Share	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Calculation of Earnings Per Share	Calculation of Earnings Per Share Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands, except shares and per share data) Calculation of Basic Earnings Per Share: Income from Continuing Operations $ 12,484 $ 9,280 $ 60,771 $ 48,981 Income/(Loss) from Discontinued Operations (9) (19) (17) 165 Net Income $ 12,475 $ 9,261 $ 60,754 $ 49,146 Weighted average shares outstanding 17,582,115 16,533,748 17,538,461 16,466,106 Basic Earnings Per Share from Continuing Operations $ 0.71 $ 0.56 $ 3.46 $ 2.97 Basic Earnings Per Share from Discontinued Operations — — — 0.01 Basic Earnings Per Share $ 0.71 $ 0.56 $ 3.46 $ 2.98 Calculation of Diluted Earnings Per Share: Reconciliation of Denominator: Weighted shares outstanding—Basic 17,582,115 16,533,748 17,538,461 16,466,106 Effect of dilutive securities—Share-based compensation 77,528 59,094 71,697 57,094 Adjusted denominator—Diluted 17,659,643 16,592,842 17,610,158 16,523,200 Diluted Earnings Per Share from Continuing Operations $ 0.71 $ 0.56 $ 3.45 $ 2.96 Diluted Earnings Per Share from Discontinued Operations — — — 0.01 Diluted Earnings Per Share $ 0.71 $ 0.56 $ 3.45 $ 2.97

Acquisitions and Divestitures (

Acquisitions and Divestitures (Notes)	9 Months Ended
	Sep. 30, 2021
Discontinued Operations and Disposal Groups [Abstract]
Business Combination Disclosure [Text Block]	3. Acquisitions Acquisition of Western Natural Gas In October 2020, Sharp acquired certain propane operating assets of Western Natural Gas, which provides propane distribution service throughout Jacksonville, Florida and the surrounding communities, for approximately $6.7 million, net of cash acquired. Additionally, the purchase price included $0.3 million of working capital. We recorded contingent consideration of $0.3 million related to the seller's adherence to various provisions contained in the purchase agreement through the first anniversary of the transaction closing. We accounted for this acquisition as a business combination within our Unregulated Energy segment beginning in the fourth quarter of 2020. There are multiple strategic benefits to this acquisition including: (i) expansion of our propane territory serviced in Florida and (ii) establishment of a customer base with additional opportunities for future growth. In connection with this acquisition, we recorded $3.5 million in property plant and equipment, $1.4 million in intangible assets associated with customer relationships and non-compete agreements and $1.8 million in goodwill, all of which is deductible for income tax purposes. The amounts recorded in conjunction with the acquisition are preliminary, and subject to adjustment based on contractual provisions. The purchase price allocation will be finalized in the fourth quarter of 2021. For the three months ended September 30, 2021, Western Natural Gas generated operating revenue and income of $0.5 million and $0.1 million, respectively. For the nine months ended September 30, 2021, Western Natural Gas generated operating revenue and income of $1.9 million and $0.4 million, respectively. Acquisition of Elkton Gas In July 2020, we closed on the acquisition of Elkton Gas, which provides natural gas distribution service to approximately 7,000 residential and commercial customers within a franchised area of Cecil County, Maryland for approximately, $15.6 million, net of cash acquired. Additionally, the purchase price included $0.6 million of working capital. Elkton Gas’ territory is contiguous to our franchised service territory in Cecil County, Maryland.

Revenue Recognition (Notes)

Revenue Recognition (Notes)	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customer [Text Block]	Revenue Recognition We recognize revenue when our performance obligations under contracts with customers have been satisfied, which generally occurs when our businesses have delivered or transported natural gas, electricity or propane to customers. We exclude sales taxes and other similar taxes from the transaction price. Typically, our customers pay for the goods and/or services we provide in the month following the satisfaction of our performance obligation. The following table displays our revenue from continuing operations by major source based on product and service type for the three months ended September 30, 2021 and 2020: Three months ended September 30, 2021 Three months ended September 30, 2020 (in thousands) Regulated Energy Unregulated Energy Other and Eliminations Total Regulated Energy Unregulated Energy Other and Eliminations Total Energy distribution Delaware natural gas division $ 7,849 $ — $ — $ 7,849 $ 7,243 $ — $ — $ 7,243 Florida natural gas division 8,015 — — 8,015 7,309 — — 7,309 FPU electric distribution 23,121 — — 23,121 29,051 — — 29,051 FPU natural gas distribution 22,012 — — 22,012 19,935 — — 19,935 Maryland natural gas division 2,432 — — 2,432 2,824 — — 2,824 Sandpiper natural gas/propane operations 3,553 — — 3,553 3,290 — — 3,290 Elkton Gas 915 — — 915 623 — — 623 Total energy distribution 67,897 — — 67,897 70,275 — — 70,275 Energy transmission Aspire Energy — 5,255 — 5,255 — 3,449 — 3,449 Aspire Energy Express 47 — — 47 — — — — Eastern Shore 18,558 — — 18,558 18,389 — — 18,389 Peninsula Pipeline 6,776 — — 6,776 6,433 — — 6,433 Total energy transmission 25,381 5,255 — 30,636 24,822 3,449 — 28,271 Energy generation Eight Flags — 4,583 — 4,583 — 3,882 — 3,882 Propane operations Propane delivery operations — 20,680 — 20,680 — 13,710 — 13,710 Energy delivery services Marlin Gas Services — 1,678 — 1,678 — 1,708 — 1,708 Other and eliminations Eliminations (12,882) (87) (5,302) (18,271) (12,335) (35) (4,188) (16,558) Other — — 132 132 — — 131 131 Total other and eliminations (12,882) (87) (5,170) (18,139) (12,335) (35) (4,057) (16,427) Total operating revenues (1) $ 80,396 $ 32,109 $ (5,170) $ 107,335 $ 82,762 $ 22,714 $ (4,057) $ 101,419 (1) Total operating revenues for the three months ended September 30, 2021, include other revenue (revenues from sources other than contracts with customers) of $0.1 million for both Regulated and Unregulated Energy segments, respectively, and $0.2 million and $0.05 million for our Regulated and Unregulated Energy segments, respectively, for the three months ended September 30, 2020. The sources of other revenues include revenue from alternative revenue programs related to revenue normalization for the Maryland division and Sandpiper Energy and late fees. The following table displays our revenue from continuing operations by major source based on product and service type for the nine months ended September 30, 2021 and 2020: Nine months ended September 30, 2021 Nine months ended September 30, 2020 (in thousands) Regulated Energy Unregulated Energy Other and Eliminations Total Regulated Energy Unregulated Energy Other and Eliminations Total Energy distribution Delaware natural gas division $ 51,188 $ — $ — $ 51,188 $ 45,568 $ — $ — $ 45,568 Florida natural gas division 25,417 — — 25,417 23,018 — — 23,018 FPU electric distribution 60,569 — — 60,569 58,972 — — 58,972 FPU natural gas distribution 72,032 — — 72,032 64,877 — — 64,877 Maryland natural gas division 16,122 — — 16,122 15,941 — — 15,941 Sandpiper natural gas/propane operations 15,438 — — 15,438 12,440 — — 12,440 Elkton Gas 4,745 — — 4,745 623 — — 623 Total energy distribution 245,511 — — 245,511 221,439 — — 221,439 Energy transmission Aspire Energy — 23,738 — 23,738 — 17,784 — 17,784 Aspire Energy Express 140 — — 140 — — — — Eastern Shore 57,147 — — 57,147 55,944 — — 55,944 Peninsula Pipeline 19,853 — — 19,853 16,618 — — 16,618 Total energy transmission 77,140 23,738 — 100,878 72,562 17,784 — 90,346 Energy generation Eight Flags — 13,086 — 13,086 — 11,898 — 11,898 Propane operations Propane delivery operations — 99,041 — 99,041 — 69,593 — 69,593 Energy delivery services Marlin Gas Services — 6,019 — 6,019 — 5,266 — 5,266 Other and eliminations Eliminations (40,148) (242) (14,937) (55,327) (34,766) (75) (12,937) (47,778) Other — 396 396 — — 396 396 Total other and eliminations (40,148) (242) (14,541) (54,931) (34,766) (75) (12,541) (47,382) Total operating revenues (1) $ 282,503 $ 141,642 $ (14,541) $ 409,604 $ 259,235 $ 104,466 $ (12,541) $ 351,160 (1) Total operating revenues for the nine months ended September 30, 2021, include other revenue (revenues from sources other than contracts with customers) of $(0.1) million and $0.3 million for our Regulated and Unregulated Energy segments, respectively, and $1.0 million and $0.2 million for our Regulated and Unregulated Energy segments, respectively, for the nine months ended September 30, 2020. The sources of other revenues include revenue from alternative revenue programs related to revenue normalization for the Maryland division and Sandpiper Energy and late fees. Contract balances The timing of revenue recognition, customer billings and cash collections results in trade receivables, unbilled receivables (contract assets), and customer advances (contract liabilities) in our condensed consolidated balance sheets. The balances of our trade receivables, contract assets, and contract liabilities as of September 30, 2021 and December 31, 2020 were as follows: Trade Receivables Contract Assets (Current) Contract Assets (Non-current) Contract Liabilities (Current) (in thousands) Balance at 12/31/2020 $ 55,600 $ 18 $ 4,816 $ 644 Balance at 9/30/2021 40,683 18 5,011 874 Increase (decrease) $ (14,917) $ — $ 195 $ 230 Our trade receivables are included in trade and other receivables in the condensed consolidated balance sheets. Our current contract assets are included in other current assets in the condensed consolidated balance sheet. Our non-current contract assets are included in other assets in the condensed consolidated balance sheet and primarily relate to operations and maintenance costs incurred by Eight Flags that have not yet been recovered through rates for the sale of electricity to our electric distribution operation pursuant to a long-term service agreement. At times, we receive advances or deposits from our customers before we satisfy our performance obligation, resulting in contract liabilities. Contract liabilities are included in other accrued liabilities in the condensed consolidated balance sheets and relate to non-refundable prepaid fixed fees for our Mid-Atlantic propane delivery operation's retail offerings. Our performance obligation is satisfied over the term of the respective retail-offering plan on a ratable basis. For the three months ended September 30, 2021 and 2020, we recognized revenue of $0.2 million. For each of the nine months ended September 30, 2021 and 2020, we recognized revenue of $0.8 million, respectively. Remaining performance obligations Our businesses have long-term fixed fee contracts with customers in which revenues are recognized when performance obligations are satisfied over the contract term. Revenue for these businesses for the remaining performance obligations, at September 30, 2021, are expected to be recognized as follows: (in thousands) 2021 2022 2023 2024 2025 2026 2027 and thereafter Eastern Shore and Peninsula Pipeline $ 9,471 $ 32,796 $ 25,205 $ 22,975 $ 22,102 $ 21,023 $ 179,728 Natural gas distribution operations 1,752 6,620 6,044 5,811 5,271 5,064 33,448 FPU electric distribution 163 652 652 652 275 275 550 Total revenue contracts with remaining performance obligations $ 11,386 $ 40,068 $ 31,901 $ 29,438 $ 27,648 $ 26,362 $ 213,726

Rates and Other Regulatory Acti

Rates and Other Regulatory Activities	9 Months Ended
	Sep. 30, 2021
Regulated Operations [Abstract]
Public Utilities Disclosure [Text Block]	Rates and Other Regulatory Activities Our natural gas and electric distribution operations in Delaware, Maryland and Florida are subject to regulation by their respective PSC; Eastern Shore, our natural gas transmission subsidiary, is subject to regulation by the FERC; and Peninsula Pipeline and Aspire Energy Express, our intrastate pipeline subsidiaries, are subject to regulation (excluding cost of service) by the Florida PSC and Public Utilities Commission of Ohio, respectively. Delaware See the discussion below under COVID-19 impact . Maryland Strategic Infrastructure Development and Enhancement (“STRIDE”) plan: In March 2021, Elkton Gas filed a strategic infrastructure development and enhancement plan with the Maryland PSC. The STRIDE plan accelerates Elkton Gas' Aldyl-A pipeline replacement program as costs of the plan are recovered through a fixed charge rider which is effective for five years. Under Elkton Gas’ STRIDE plan, the Aldyl-A pipelines will be fully replaced by 2023. In July 2021, Elkton Gas reached a settlement with the Maryland PSC Staff and the Maryland Office of Public Counsel that approved Elkton Gas’ STRIDE plan. The STRIDE plan allows for recovery of the associated revenue requirement through a monthly surcharge, which was implemented effective September 4, 2021. Florida Hurricane Michael: In late 2019, the Florida PSC approved an interim rate increase for FPU electric division's limited proceeding, subject to refund, effective January 1, 2020, associated with the restoration effort following Hurricane Michael. We fully reserved these interim rates, pending a final resolution and settlement. In September 2020, the Florida PSC approved a settlement agreement between FPU and the Florida OPC regarding final cost recovery and rates associated with Hurricane Michael. The settlement agreement allowed us to: (a) refund the over-collection of interim rates through the fuel clause; (b) record regulatory assets for storm costs in the amount of $45.8 million including interest which will be amortized over six years; (c) recover these storm costs through a surcharge for a total of $7.7 million annually; and (d) collect an annual increase in revenue of $3.3 million to recover capital costs associated with new plant and a regulatory asset for cost of removal and undepreciated plant. The new base rates and storm surcharge were effective on November 1, 2020. Electric Depreciation Study: In September 2019, FPU filed a petition, with the Florida PSC, for approval of its consolidated electric depreciation rates. The petition was joined to the Hurricane Michael docket, and was approved at the Florida PSC Agenda in September 2020. The approved rates were retroactively applied effective January 1, 2020. West Palm Beach Expansion Project: In August 2019, the Florida PSC approved Peninsula Pipeline’s Transportation Service Agreement with FPU. Peninsula Pipeline is constructing several new interconnection points and pipeline expansions in Palm Beach County, Florida, which will enable FPU to serve an industrial research park and several new residential developments. Peninsula Pipeline will provide transportation service to FPU, increasing reliability and system pressure as well as introducing diversity in the fuel source for natural gas to serve the increased demand in these areas. Interim services began in the fourth quarter of 2019 and we expect to complete the remainder of the project in phases through the fourth quarter of 2021. Winter Haven Expansion Project: In May 2021, Peninsula Pipeline filed a petition with the Florida PSC for approval of its Transportation Service Agreement with CFG for an incremental 6,800 Dts/d of firm service in the Winter Haven, Florida area. As part of this agreement, Peninsula Pipeline will construct a new interconnect with FGT and a new regulator station for CFG. CFG will use the additional firm service to support new incremental load due to growth, including providing service to a new can manufacturing facility, as well as provide reliability and operational benefits to CFG’s existing distribution system in the area. In connection with Peninsula Pipeline’s new regulator station, CFG is also extending its distribution system to connect to the new station. The Transportation Service Agreement was approved by the Florida PSC in September 2021. Escambia Meter Station: In June 2021, Peninsula Pipeline purchased the Escambia Meter Station from Florida Power & Light Company and entered into a Transportation Service Agreement with Gulf Power Company for up to 530,000 Dts/d of firm service from an interconnect with FGT to Florida Power & Light Company’s Crist Lateral pipeline, which provides gas supply to their natural gas fired power plant in Pensacola, Florida. Beachside Pipeline Extension: In June 2021, Peninsula Pipeline and Florida City Gas entered into a Transportation Service Agreement for an incremental 10,176 Dts/d of firm service in Indian River County, Florida, to support Florida City Gas’ growth along the Indian River's barrier island. As part of this agreement, Peninsula Pipeline will construct 11.3 miles of pipeline from its existing pipeline in the Sebastian, Florida area, which will travel east under the Intercoastal Waterway ("ICW") and southward on the barrier island. As required by Peninsula Pipeline’s tariff and Florida Statutes, Peninsula Pipeline filed the required company and customer affidavits with the Florida PSC in June 2021. Construction commenced in June 2021 and the expected in-service date is December 2022. Eastern Shore Del-Mar Energy Pathway Project: In December 2019, the FERC issued an order approving the construction of the Del-Mar Energy Pathway project. The order approved the construction and operation of new facilities that will provide an additional 14,300 Dts/d of firm service to four customers. This includes six miles of pipeline looping in Delaware; 13 miles of new mainline extension in Sussex County, Delaware and Wicomico and Somerset Counties in Maryland; and new pressure control and delivery stations in these counties. The benefits of this project include: (i) additional natural gas transmission pipeline infrastructure in eastern Sussex County, Delaware, and (ii) extension of Eastern Shore’s pipeline system, for the first time, into Somerset County, Maryland. The project is now fully in service as the construction of the Somerset County, Maryland expansion was completed in the third quarter of 2021. Capital Cost Surcharge: In June 2021, Eastern Shore submitted a filing with the FERC regarding a capital cost surcharge to recover capital costs associated with two mandated highway relocate projects that required the replacement of existing Eastern Shore facilities. The capital cost surcharge is an approved item in the settlement of Eastern Shore’s last rate case. In conjunction with the filing of this surcharge, pursuant to the settlement agreement, a cumulative adjustment to the existing surcharge to reflect additional depreciation was included in this filing. The FERC issued an order approving the surcharge as filed on July 7, 2021. The combined revised surcharge became effective July 15, 2021. COVID-19 Impact In March 2020, the CDC declared a national emergency due to the rapidly growing outbreak of COVID-19. In response to this declaration and the rapid spread of COVID-19 within the United States, federal, state and local governments throughout the country imposed varying degrees of restrictions on social and commercial activity to promote social distancing in an effort to slow the spread of the illness. These restrictions significantly impacted economic conditions in the United States in 2020 and have continued through the third quarter of 2021. Chesapeake Utilities is considered an “essential business,” which has allowed us to continue operational activities and construction projects with appropriate safety precautions and personal protective equipment, while being mindful of the social distancing restrictions that were in place. In response to the COVID-19 pandemic and related restrictions, we experienced reduced consumption of energy largely in the commercial and industrial sectors, higher bad debt expenses and incremental expenses associated with COVID-19, including expenditures associated with personal protective equipment and premium pay for field personnel. The additional operating expenses we incurred support the ongoing delivery of our essential services during these unprecedented times. At this time, restrictions are gradually being lifted as vaccines are widely available in the United States. The state of emergency in Florida was terminated in May followed by Delaware and Maryland in July. Despite these positive state orders and in light of the prevalence of new variants of COVID-19, we continue to operate under our pandemic response plan, monitor developments affecting employees, customers, suppliers, stockholders and take all precautions warranted to operate safely and to comply with the CDC and the Occupational Safety and Health Administration, with a goal of minimizing further exposure for our employees, customers and the communities. In April 2020, the Maryland PSC issued an order that authorized utilities to establish a regulatory asset to record prudently incurred incremental costs related to COVID-19, beginning on March 16, 2020. The Maryland PSC found that the creation of a regulatory asset for COVID-19 related expenses will facilitate the recovery of those costs prudently incurred to serve customers during the COVID-19 pandemic, and that the deferral of such costs is appropriate because the current catastrophic health emergency is outside the control of the utility and is a non-recurring event. The Maryland PSC has reviewed and issued guidance regarding the distribution of funds and the manner in which the utilities will allocate the funds to customers with eligible arrearages. Chesapeake Utilities – Maryland Division, Sandpiper Energy, and Elkton Gas received $0.3 million in the third quarter of 2021 to credit the accounts of those customers experiencing financial hardship in becoming current on their past due balances. In May 2020, the Delaware PSC issued an order that authorized Delaware utilities to establish a regulatory asset to record COVID-19 related incremental costs incurred to ensure customers have essential utility services, for the period beginning on March 24, 2020 and ending 30 days after the state of emergency ends. The state of emergency was lifted July 12, 2021. The creation of the regulatory asset for COVID-19 related costs offers utilities the ability to seek recovery of those costs. Funds to assist with individual customer arrearages have become available through the Delaware State Housing Authority. We are working to ensure that customers know how to seek this support and then apply it to their overdue utility bills. In October 2020, the Florida PSC approved a joint petition of our natural gas and electric distribution utilities in Florida to establish a regulatory asset to record incremental expenses incurred due to COVID-19. The regulatory asset will allow us to seek recovery of these costs in the next base rate proceedings. In November 2020, the Florida OPC filed a protest to the order approving the establishment of this regulatory asset treatment, contending that the order should be reversed or modified and to request a hearing on the protest. The Company’s Florida regulated business units reached a settlement with the Florida OPC in June 2021. The settlement allows the units to establish a regulatory asset in a total amount of $2.1 million as of June 30, 2021. This amount includes COVID-19 related incremental expenses for bad debt write-offs, personnel protective equipment, cleaning and business information services for remote work. Our Florida regulated business units will amortize the regulatory asset over two years and recover it through the Purchased Gas Adjustment and Swing Service mechanisms for the natural gas business units and through the Fuel Purchased Power Cost Recovery clause for the electric division. This settlement agreement was approved by the Florida PSC on July 8, 2021 and the final order was issued on July 22, 2021. In the fourth quarter of 2020, we began recording regulatory assets based on the net incremental expense resulting from the COVID-19 pandemic for our natural gas distribution and electric business units as authorized by the Delaware, Maryland and Florida PSCs. As of September 30, 2021 and December 31, 2020, our total COVID-19 regulatory asset balance was $2.3 million and $1.9 million, respectively. Summary TCJA Table Customer rates for our regulated businesses were adjusted as approved by the regulators, prior to 2020 with the exception of Elkton Gas, which implemented a one-time bill credit in May 2020. The following table summarizes the regulatory liabilities related to accumulated deferred taxes ("ADIT") associated with TCJA for our regulated businesses as of September 30, 2021 and December 31, 2020: Amount (in thousands) Operation and Regulatory Jurisdiction September 30, 2021 December 31, 2020 Status Eastern Shore (FERC) $34,190 $34,190 Will be addressed in Eastern Shore's next rate case filing. Delaware Division (Delaware PSC) $12,626 $12,728 PSC approved amortization of ADIT in January 2019. Maryland Division (Maryland PSC) $3,873 $3,970 PSC approved amortization of ADIT in May 2018. Sandpiper Energy (Maryland PSC) $3,670 $3,713 PSC approved amortization of ADIT in May 2018. Chesapeake Florida Gas Division/Central Florida Gas (Florida PSC) $8,070 $8,184 PSC issued order authorizing amortization and retention of net ADIT liability by the Company in February 2019. FPU Natural Gas (excludes Fort Meade and Indiantown) (Florida PSC) $19,132 $19,257 Same treatment on a net basis as Chesapeake Florida Gas Division (above). FPU Fort Meade and Indiantown Divisions $274 $309 Same treatment on a net basis as Chesapeake Florida Gas Division (above). FPU Electric (Florida PSC) $5,299 $6,694 In January 2019, PSC issued order approving amortization of ADIT through purchased power cost recovery, storm reserve and rates. Elkton Gas (Maryland PSC) $1,124 $1,124 PSC approved amortization of ADIT in March 2018.

Environmental Commitments and C

Environmental Commitments and Contingencies	9 Months Ended
	Sep. 30, 2021
Environmental Remediation Obligations [Abstract]
Environmental Commitments and Contingencies	Environmental Commitments and Contingencies We are subject to federal, state and local laws and regulations governing environmental quality and pollution control. These laws and regulations require us to remove or remediate, at current and former operating sites, the effect on the environment of the disposal or release of specified substances. MGP Sites We have participated in the investigation, assessment or remediation of, and have exposures at, seven former MGP sites. We have received approval for recovery of clean-up costs in rates for sites located in Salisbury, Maryland; Seaford, Delaware; and Winter Haven, Key West, Pensacola, Sanford and West Palm Beach, Florida. As of September 30, 2021 and December 31, 2020, we had approximately $5.4 million and $5.9 million, respectively, in environmental liabilities related to FPU’s four MGP sites in Key West, Pensacola, Sanford and West Palm Beach. FPU has approval to recover, from insurance and through customer rates, up to $14.0 million of its environmental costs related to its MGP sites. As of September 30, 2021 and December 31, 2020, we had recovered approximately $12.7 million and $12.4 million, respectively, leaving approximately $1.3 million and $1.6 million, respectively, in regulatory assets for future recovery of environmental costs from FPU’s customers. Environmental liabilities for our MGP sites are recorded on an undiscounted basis based on the estimate of future costs provided by independent consultants. We continue to expect that all costs related to environmental remediation and related activities, including any potential future remediation costs for which we do not currently have approval for regulatory recovery, will be recoverable from customers through rates. Remediation is ongoing for the MGPs in Winter Haven and Key West in Florida and in Seaford, Delaware and the remaining clean-up costs are estimated to be between $0.3 million to $0.9 million for these three sites. The Environmental Protection Agency has approved a "site-wide ready for anticipated use" status for the Sanford, Florida MGP site, which is the final step before delisting a site. The remaining remediation expenses for the Sanford MGP site are immaterial. The following is a summary of our remediation status and estimated costs to implement clean-up of our West Palm Beach Florida site: Status Estimated Clean-Up Costs Remedial actions approved by the Florida Department of Environmental Protection have been implemented on the east parcel of the site. Similar remedial actions have been initiated on the site's west parcel, and construction of active remedial systems are expected be completed in 2022. Between $3.3 million to $14.2 million, including costs associated with the relocation of FPU’s operations at this site, and any potential costs associated with future redevelopment of the properties.

Other Commitments and Contingen

Other Commitments and Contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Other Commitments and Contingencies	Other Commitments and Contingencies Natural Gas and Electric In March 2020, our Delmarva Peninsula natural gas distribution operations entered into asset management agreements with a third party to manage their natural gas transportation and storage capacity. The agreements were effective as of April 1, 2020 and expire in March 2023. FPU natural gas distribution operations and Eight Flags have separate asset management agreements with Emera Energy Services, Inc. to manage their natural gas transportation capacity. These agreements are for a 10-year term that commenced in November 2020 and expire in October 2030. Chesapeake Utilities' Florida Division has firm transportation service contracts with FGT and Gulfstream. Pursuant to a capacity release program approved by the Florida PSC, all of the capacity under these agreements has been released to various third parties. Under the terms of these capacity release agreements, Chesapeake Utilities is contingently liable to FGT and Gulfstream should any party, that acquired the capacity through release, fail to pay the capacity charge. To date, Chesapeake Utilities has not been required to make a payment resulting from this contingency. FPU’s electric supply contracts require FPU to maintain an acceptable standard of creditworthiness based on specific financial ratios. FPU’s agreement with Florida Power & Light Company requires FPU to meet or exceed a debt service coverage ratio of 1.25 times based on the results of the prior 12 months. If FPU fails to meet this ratio, it must provide an irrevocable letter of credit or pay all amounts outstanding under the agreement within five business days. FPU’s electric supply agreement with Gulf Power requires FPU to meet the following ratios based on the average of the prior six quarters: (a) funds from operations interest coverage ratio (minimum of two times), and (b) total debt to total capital (maximum of 65 percent). If FPU fails to meet the requirements, it has to provide the supplier a written explanation of actions taken, or proposed to be taken, to become compliant. Failure to comply with the ratios specified in the Gulf Power agreement could also result in FPU having to provide an irrevocable letter of credit. As of September 30, 2021, FPU was in compliance with all of the requirements of its fuel supply contracts. Eight Flags provides electricity and steam generation services through its CHP plant located on Amelia Island, Florida. In June 2016, Eight Flags began selling power generated from the CHP plant to FPU pursuant to a 20-year power purchase agreement for distribution to our electric customers. In July 2016, Eight Flags also started selling steam, pursuant to a separate 20-year contract, to the landowner on which the CHP plant is located. The CHP plant is powered by natural gas transported by FPU through its distribution system and Peninsula Pipeline through its intrastate pipeline. Corporate Guarantees The Board of Directors has authorized us to issue corporate guarantees securing obligations of our subsidiaries and to obtain letters of credit securing our subsidiaries' obligations. The maximum authorized liability under such guarantees and letters of credit as of September 30, 2021 was $20.0 million. The aggregate amount guaranteed at September 30, 2021 was approximately $8.0 million with the guarantees expiring on various dates through September 24, 2022.

Segment Information

Segment Information	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Segment Information	Segment Information We use the management approach to identify operating segments. We organize our business around differences in regulatory environment and the operating results of each segment are regularly reviewed by the chief operating decision maker, our Chief Executive Officer, in order to make decisions about resources and to assess performance. Our operations are entirely domestic and are comprised of two reportable segments: • Regulated Energy . Includes energy distribution and transmission services (natural gas distribution, natural gas transmission and electric distribution operations). All operations in this segment are regulated, as to their rates and services, by the PSC having jurisdiction in each operating territory or by the FERC in the case of Eastern Shore. • Unregulated Energy. Includes energy transmission, energy generation (the operations of our Eight Flags' CHP plant), propane operations, and mobile compressed natural gas distribution and pipeline solutions subsidiary. Also included in this segment are other unregulated energy services, such as energy-related merchandise sales and heating, ventilation and air conditioning, plumbing and electrical services. These operations are unregulated as to their rates and services. Effective in the third quarter of 2019, the natural gas marketing and related services subsidiary (PESCO), previously reported in the Unregulated Energy segment, was reflected in discontinued operations. The remainder of our operations is presented as “Other businesses and eliminations,” which consists of unregulated subsidiaries that own real estate leased to Chesapeake Utilities, as well as certain corporate costs not allocated to other operations. The following table presents financial information about our reportable segments: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Operating Revenues, Unaffiliated Customers Regulated Energy $ 79,892 $ 82,297 $ 280,987 $ 257,810 Unregulated Energy 27,443 19,122 128,617 93,350 Total operating revenues, unaffiliated customers $ 107,335 $ 101,419 $ 409,604 $ 351,160 Intersegment Revenues (1) Regulated Energy $ 504 $ 465 $ 1,516 $ 1,425 Unregulated Energy 4,666 3,592 13,024 11,116 Other businesses 132 131 397 396 Total intersegment revenues $ 5,302 $ 4,188 $ 14,937 $ 12,937 Operating Income Regulated Energy $ 23,538 $ 20,482 $ 79,210 $ 66,376 Unregulated Energy (2,883) (3,092) 15,777 11,050 Other businesses and eliminations (542) 16 (699) 92 Operating income 20,113 17,406 94,288 77,518 Other income (expense), net 339 (40) 2,180 2,997 Interest charges 4,975 4,584 15,134 15,452 Income from Continuing Operations before Income Taxes 15,477 12,782 81,334 65,063 Income Taxes on Continuing Operations 2,993 3,502 20,563 16,082 Income from Continuing Operations 12,484 9,280 60,771 48,981 Income (Loss) from Discontinued Operations, Net of Tax (9) (19) (17) 165 Net Income $ 12,475 $ 9,261 $ 60,754 $ 49,146 (1) All significant intersegment revenues are billed at market rates and have been eliminated from consolidated operating revenues. (in thousands) September 30, 2021 December 31, 2020 Identifiable Assets Regulated Energy segment $ 1,592,950 $ 1,547,619 Unregulated Energy segment 381,642 347,665 Other businesses and eliminations 47,236 37,203 Total identifiable assets $ 2,021,828 $ 1,932,487

Stockholder's Equity - Accumula

Stockholder's Equity - Accumulated Other Comprehensive Income (Loss)	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Accumulated Other Comprehensive Income (Loss)	Stockholders' Equity Common Stock Issuances In June 2020, we filed a shelf registration statement with the SEC to facilitate the issuance of our common stock from time to time. In August 2020, we filed a prospectus supplement under the shelf registration statement for an ATM equity program under which we may issue and sell shares of our common stock up to an aggregate offering price of $75.0 million. In the third and fourth quarters of 2020, we issued 0.7 million shares of common stock at an average price per share of $82.93 and received net proceeds of approximately $61.0 million, after deducting commissions and other fees of $1.5 million. We maintain an effective shelf registration statement with the SEC for the issuance of shares under our DRIP. Depending on our capital needs and subject to market conditions, in addition to other possible debt and equity offerings, we may issue additional shares under the direct stock purchase component of the DRIP. In the third and fourth quarters of 2020, we issued 0.3 million shares at an average price per share of $86.12 and received net proceeds of $22.0 million under the DRIP. In the first nine months of 2021, we issued less than 0.1 million shares at an average price per share of $116.63 and received net proceeds of $6.6 million under the DRIP. In October 2021, we issued less than 0.1 million shares at an average price per share of $127.40 and received net proceeds of $1.8 million under the DRIP. We used the net proceeds from the ATM equity program and the DRIP, after deducting the commissions or other fees and related offering expenses payable by us, for general corporate purposes, including, but not limited to, financing of capital expenditures, repayment of short-term debt, financing acquisitions, investing in subsidiaries, and general working capital purposes. Accumulated Other Comprehensive Gain (Loss) Defined benefit pension and postretirement plan items, unrealized gains (losses) of our propane swap agreements designated as commodity contracts cash flow hedges, and the unrealized gains (losses) of our interest rate swap agreements designated as cash flow hedges are the components of our accumulated other comprehensive income (loss). The following tables present the changes in the balance of accumulated other comprehensive gain (loss) as of September 30, 2021 and 2020. All amounts in the following tables are presented net of tax. Defined Benefit Commodity Interest Rate Pension and Contracts Swap Postretirement Cash Flow Cash Flow Plan Items Hedges Hedges Total (in thousands) As of December 31, 2020 $ (5,146) $ 2,309 $ (28) $ (2,865) Other comprehensive income before reclassifications — 8,121 55 8,176 Amounts reclassified from accumulated other comprehensive income (loss) 192 (3,027) (37) (2,872) Net current-period other comprehensive income 192 5,094 18 5,304 As of September 30, 2021 $ (4,954) $ 7,403 $ (10) $ 2,439 (in thousands) As of December 31, 2019 $ (4,933) $ (1,334) $ — $ (6,267) Other comprehensive income before reclassifications — 3,594 23 3,617 Amounts reclassified from accumulated other comprehensive income/(loss) 198 (1,144) (33) (979) Net prior-period other comprehensive income/(loss) 198 2,450 (10) 2,638 As of September 30, 2020 $ (4,735) $ 1,116 $ (10) $ (3,629) The following table presents amounts reclassified out of accumulated other comprehensive income (loss) for the three and nine months ended September 30, 2021 and 2020. Deferred gains or losses for our commodity contracts and interest rate swap cash flow hedges are recognized in earnings upon settlement. Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Amortization of defined benefit pension and postretirement plan items: Prior service credit (1) $ 19 $ 19 $ 57 $ 57 Net loss (1) (106) (108) (317) (323) Total before income taxes (87) (89) (260) (266) Income tax benefit 23 23 68 68 Net of tax $ (64) $ (66) $ (192) $ (198) Gains on commodity contracts cash flow hedges: Propane swap agreements (2) $ 681 $ 116 $ 4,183 $ 1,581 Income tax expense (188) (32) (1,156) (437) Net of tax $ 493 $ 84 $ 3,027 $ 1,144 Gains on interest rate swap cash flow hedges: Interest rate swap agreements $ 24 $ 34 $ 50 $ 45 Income tax expense (6) (9) (13) (12) Net of tax $ 18 $ 25 $ 37 $ 33 Total reclassifications for the period $ 447 $ 43 $ 2,872 $ 979 (1) These amounts are included in the computation of net periodic costs (benefits). See Note 10 , Employee Benefit Plans , for additional details. (2) These amounts are included in the effects of gains and losses from derivative instruments. See Note 13, Derivative Instruments , for additional details. Amortization of defined benefit pension and postretirement plan items are included in other expense, net gains and losses on propane swap agreements contracts are included in cost of sales, the realized gain or loss on interest rate swap agreements is recognized as a component of interest charges in the accompanying condensed consolidated statements of income. The income tax benefit is included in income tax expense in the accompanying condensed consolidated statements of income.

Employee Benefit Plans

Employee Benefit Plans	9 Months Ended
	Sep. 30, 2021
Retirement Benefits [Abstract]
Employee Benefit Plans	Employee Benefit PlansNet periodic benefit costs for our pension and post-retirement benefits plans for the three and nine months ended September 30, 2021 and 2020 are set forth in the following tables: Chesapeake FPU Chesapeake SERP Chesapeake FPU For the Three Months Ended September 30, 2021 2020 2021 2020 2021 2020 2021 2020 2021 2020 (in thousands) Interest cost $ 34 $ 46 $ 429 $ 518 $ 12 $ 16 $ 6 $ 8 $ 6 $ 10 Expected return on plan assets (40) (42) (830) (745) — — — — — — Amortization of prior service credit — — — — — — (19) (19) — — Amortization of net (gain) loss 60 65 155 135 7 5 10 12 (2) — Net periodic cost (benefit) 54 69 (246) (92) 19 21 (3) 1 4 10 Amortization of pre-merger regulatory asset — — — — — — — — — 2 Total periodic cost (benefit) $ 54 $ 69 $ (246) $ (92) $ 19 $ 21 $ (3) $ 1 $ 4 $ 12 Chesapeake FPU Chesapeake SERP Chesapeake FPU For the Nine Months Ended September 30, 2021 2020 2021 2020 2021 2020 2021 2020 2021 2020 (in thousands) Interest cost $ 102 $ 138 $ 1,287 $ 1,554 $ 36 $ 48 $ 18 $ 24 $ 18 $ 30 Expected return on plan assets (120) (126) (2,490) (2,235) — — — — — — Amortization of prior service credit — — — — — — (57) (57) — — Amortization of net (gain) loss 180 195 465 405 21 15 30 36 (6) — Net periodic cost (benefit) 162 207 (738) (276) 57 63 (9) 3 12 30 Amortization of pre-merger regulatory asset — — — — — — — — — 6 Total periodic cost (benefit) $ 162 $ 207 $ (738) $ (276) $ 57 $ 63 $ (9) $ 3 $ 12 $ 36 In 2019, we began executing a de-risking strategy for the Chesapeake Pension Plan. In line with this strategy, we have decided to fully terminate the Chesapeake Pension Plan, which we expect to be complete in the fourth quarter of 2021 and will recognize the necessary expense associated with the termination of the Chesapeake Pension Plan at that time. The components of our net periodic costs have been recorded or reclassified to other expense, net in the condensed consolidated statements of income. Pursuant to their respective regulatory orders, FPU and Chesapeake Utilities continue to record, as a regulatory asset, a portion of their unrecognized postretirement benefit costs related to their regulated operations. The portion of the unrecognized pension and postretirement benefit costs related to FPU’s unregulated operations and Chesapeake Utilities' operations is recorded to accumulated other comprehensive income. The following tables present the amounts included in the regulatory asset and accumulated other comprehensive income that were recognized as components of net periodic benefit cost during the three and nine months ended September 30, 2021 and 2020: For the Three Months Ended September 30, 2021 Chesapeake FPU Chesapeake SERP Chesapeake FPU Total (in thousands) Prior service credit $ — $ — $ — $ (19) $ — $ (19) Net loss 60 155 7 10 (2) 230 Total recognized in net periodic benefit cost 60 155 7 (9) (2) 211 Recognized from accumulated other comprehensive (income)/loss (1) 60 29 7 (9) — 87 Recognized from regulatory asset — 126 — — (2) 124 Total $ 60 $ 155 $ 7 $ (9) $ (2) $ 211 For the Three Months Ended September 30, 2020 Chesapeake FPU Chesapeake SERP Chesapeake FPU Total (in thousands) Prior service credit $ — $ — $ — $ (19) $ — $ (19) Net loss 65 135 5 12 — 217 Total recognized in net periodic benefit cost 65 135 5 (7) — 198 Recognized from accumulated other comprehensive (income)/loss (1) 65 26 5 (7) — 89 Recognized from regulatory asset — 109 — — — 109 Total $ 65 $ 135 $ 5 $ (7) $ — $ 198 For the Nine Months Ended September 30, 2021 Chesapeake FPU Chesapeake SERP Chesapeake FPU Total (in thousands) Prior service credit $ — $ — $ — $ (57) $ — $ (57) Net loss 180 465 21 30 (6) 690 Total recognized in net periodic benefit cost 180 465 21 (27) (6) 633 Recognized from accumulated other comprehensive (income)/loss (1) 180 87 21 (27) (1) 260 Recognized from regulatory asset — 378 — — (5) 373 Total $ 180 $ 465 $ 21 $ (27) $ (6) $ 633 For the Nine Months Ended September 30, 2020 Chesapeake FPU Chesapeake SERP Chesapeake FPU Total (in thousands) Prior service credit $ — $ — $ — $ (57) $ — $ (57) Net loss 195 405 15 36 — 651 Total recognized in net periodic benefit cost 195 405 15 (21) — 594 Recognized from accumulated other comprehensive (income)/loss (1) 195 78 15 (21) — 267 Recognized from regulatory asset — 327 — — — 327 Total $ 195 $ 405 $ 15 $ (21) $ — $ 594 (1) See Note 9 , Stockholders' Equity . During the three and nine months ended September 30, 2021, we contributed approximately $0.2 million and $0.3 million, respectively to the Chesapeake Pension Plan and approximately $0.5 million and $1.3 million, respectively, to the FPU Pension Plan. We expect to contribute approximately $2.1 million to the FPU Pension Plan during 2021, which represents the minimum annual contribution payments required. We will make all required contributions to the Chesapeake Pension Plan so that it can be terminated before the end of the year. The Chesapeake SERP, the Chesapeake Postretirement Plan and the FPU Medical Plan are unfunded and are expected to be paid out of our general funds. Cash benefits paid under the Chesapeake SERP for the three and nine months ended September 30, 2021 were immaterial and $0.1 million, respectively. We expect to pay total cash benefits of approximately $0.2 million under the Chesapeake SERP in 2021. Cash benefits paid under the Chesapeake Postretirement Plan, primarily for medical claims for the three and nine ended September 30, 2021 were immaterial and $0.2 million, respectively. We estimate that approximately $0.2 million will be paid for such benefits under the Chesapeake Postretirement Plan in 2021. Cash benefits paid under the FPU Medical Plan, primarily for medical claims for the three and nine months ended September 30, 2021, were $0.1 million. We estimate that approximately $0.1 million will be paid for such benefits under the FPU Medical Plan in 2021.

Investments

Investments	9 Months Ended
	Sep. 30, 2021
Investments, Debt and Equity Securities [Abstract]
Investments	Investments The investment balances at September 30, 2021 and December 31, 2020, consisted of the following: (in thousands) September 30, December 31, Rabbi trust (associated with the Non-Qualified Deferred Compensation Plan) $ 11,467 $ 10,755 Investments in equity securities 23 21 Total $ 11,490 $ 10,776 We classify these investments as trading securities and report them at their fair value. For the three months ended September 30, 2021 and 2020, we recorded an immaterial net unrealized loss and a net unrealized gain of $0.6 million, respectively, in other income, net in the condensed consolidated statements of income related to these investments. For the nine months ended September 30, 2021 and 2020, we recorded net unrealized gains of approximately $1.0 million and $0.4 million, respectively, in other expense, net in the condensed consolidated statements of income related to these investments. For the investment in the Rabbi Trust, we also have recorded an associated liability, which is included in other pension and benefit costs in the consolidated balance sheets and is adjusted each period for the gains and losses incurred by the investments in the Rabbi Trust.

Share-Based Compensation

Share-Based Compensation	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Share-Based Compensation	Share-Based Compensation Our non-employee directors and key employees are granted share-based awards through our SICP. We record these share-based awards as compensation costs over the respective service period for which services are received in exchange for an award of equity or equity-based compensation. The compensation cost is based primarily on the fair value of the shares awarded, using the estimated fair value of each share on the date it was granted and the number of shares to be issued at the end of the service period. The table below presents the amounts included in net income related to share-based compensation expense for the three and nine months ended September 30, 2021 and 2020: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Awards to non-employee directors $ 201 $ 188 $ 581 $ 545 Awards to key employees 1,105 1,144 4,039 3,109 Total compensation expense 1,306 1,332 4,620 3,654 Less: tax benefit (339) (348) (1,200) (955) Share-based compensation amounts included in net income $ 967 $ 984 $ 3,420 $ 2,699 Non-employee Directors Shares granted to non-employee directors are issued in advance of the directors’ service periods and are fully vested as of the grant date. We record a deferred expense equal to the fair value of the shares issued and amortize the expense equally over a service period of one year. In May 2021, after the most recent election of directors, each of our non-employee directors received an annual retainer of 683 shares of common stock under the SICP for service as a director through the 2022 Annual Meeting of Stockholders; accordingly, 6,830 shares, with a weighted average fair value of $117.11 per share, were issued and vested in 2021. At September 30, 2021, there was approximately $0.5 million of unrecognized compensation expense related to shares granted to non-employee directors. This expense will be recognized over the remaining service period ending in May of 2022. On October 15, 2021, a newly appointed member of the Board of Directors received a pro-rated retainer of 342 shares of common stock under the SICP to serve as a non-employee director through the 2022 Annual Meeting of Stockholders. The shares awarded to the non-employee director immediately vested upon issuance in October 2021, had a weighted average fair value of $129.09 per share, and will be expensed over the remaining service period ending on the date of the 2022 Annual Meeting of Stockholders. Key Employees The table below presents the summary of the stock activity for awards to key employees for the nine months ended September 30, 2021: Number of Shares Weighted Average Outstanding—December 31, 2020 186,878 $ 87.06 Granted 68,562 $ 102.73 Vested (53,147) $ 76.31 Expired (852) $ 74.85 Forfeited (5,384) $ 93.39 Outstanding—September 30, 2021 196,057 $ 94.15 During the nine months ended September 30, 2021, we granted awards of 68,562 shares of common stock to key employees under the SICP, including awards granted in February 2021 and to key employees appointed in officer positions. The shares granted are multi-year awards that will vest no later than the three-year service period ending December 31, 2023. All of these stock awards are earned based upon the successful achievement of long-term financial results, which are comprised of market-based and performance-based conditions or targets. The fair value of each performance-based condition or target is equal to the market price of our common stock on the grant date of each award. For the market-based conditions, we used the Monte Carlo valuation to estimate the fair value of each market-based award granted. In March 2021, upon the election of certain of our executive officers, we withheld shares with a value at least equivalent to each such executive officer’s minimum statutory obligation for applicable income and other employment taxes related to shares that vested and were paid in February 2021 for the performance period ended December 31, 2020, remitted the cash to the appropriate taxing authorities, and paid the balance of such awarded shares to each such executive officer. We withheld 14,020 shares, based on the value of the shares on their award date. Total combined payments for the employees’ tax obligations to the taxing authorities were approximately $1.5 million. At September 30, 2021, the aggregate intrinsic value of the SICP awards granted to key employees was approximately $23.5 million. At September 30, 2021, there was approximately $5.6 million of unrecognized compensation cost related to these awards, which will be recognized through 2023. Stock Options There were no stock options outstanding or issued during the nine months ended September 30, 2021 and 2020.

Derivative Instruments

Derivative Instruments	9 Months Ended
	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments We use derivative and non-derivative contracts to manage risks related to obtaining adequate supplies and the price fluctuations of natural gas, electricity and propane and to mitigate interest rate risk. Our natural gas, electric and propane distribution operations have entered into agreements with suppliers to purchase natural gas, electricity and propane for resale to our customers. Our natural gas gathering and transmission company has entered into contracts with producers to secure natural gas to meet its obligations. Purchases under these contracts typically either do not meet the definition of derivatives or are considered “normal purchases and normal sales” and are accounted for on an accrual basis. Our propane distribution operations may also enter into fair value hedges of their inventory or cash flow hedges of their future purchase commitments in order to mitigate the impact of wholesale price fluctuations. We have also entered into interest rate swap agreements to mitigate risk associated with changes in short-term borrowing rates. As of September 30, 2021, our natural gas and electric distribution operations did not have any outstanding derivative contracts. Volume of Derivative Activity As of September 30, 2021, the volume of our commodity derivative contracts were as follows: Business unit Commodity Contract Type Quantity hedged (in millions) Designation Longest Expiration date of hedge Sharp Propane (gallons) Purchases 23.4 Cash flows hedges June 2024 Sharp Propane (gallons) Sales 5.0 Cash flows hedges March 2022 Sharp entered into futures and swap agreements to mitigate the risk of fluctuations in wholesale propane index prices associated with the propane volumes that are expected to be purchased and/or sold during the heating season. Under the futures and swap agreements, Sharp will receive the difference between (i) the index prices (Mont Belvieu prices in September 2021 through June 2024) and (ii) the per gallon propane swap prices, to the extent the index prices exceed the contracted prices. If the index prices are lower than the swap prices, Sharp will pay the difference. We designated and accounted for the propane swaps as cash flows hedges. The change in the fair value of the swap agreements is recorded as unrealized gain (loss) in other comprehensive income (loss) and later recognized in the statement of income in the same period and in the same line item as the hedged transaction. We expect to reclassify approximately $6.2 million from accumulated other comprehensive income to earnings during the next 12-month period ended September 30, 2022. Interest Rate Swap Activities We manage interest rate risk by entering into derivative contracts to hedge the variability in cash flows attributable to changes in the short-term borrowing rates. In the fourth quarter of 2020, we entered into two $30.0 million interest rate swaps with a total notional amount of $60.0 million through September and December 2021 with pricing of 0.205 and 0.20 percent, respectively, for the period associated with our outstanding borrowing under the Revolver. In February 2021, we entered into an additional interest rate swap with a notional amount of $40.0 million through December 2021 with pricing of 0.17 percent. Our short-term borrowing is based on the 30-day LIBOR rate. The interest rate swaps are cash settled monthly as the counter-party pays us the 30-day LIBOR rate less the fixed rate. We designated and accounted for interest rate swaps as cash flows hedges. Accordingly, unrealized gains and losses associated with the interest rate swaps are recorded as a component of accumulated other comprehensive income (loss). When the interest rate swaps settle, the realized gain or loss will be recorded in the income statement and recognized as a component of interest charges. We expect to reclassify less than $0.1 million from accumulated other comprehensive (loss) to earnings during the next 12-month period ended September 30, 2022. Broker Margin Futures exchanges have contract specific margin requirements that require the posting of cash or cash equivalents relating to traded contracts. Margin requirements consist of initial margin that is posted upon the initiation of a position, maintenance margin that is usually expressed as a percent of initial margin, and variation margin that fluctuates based on the daily mark-to-market relative to maintenance margin requirements. We currently maintain a broker margin account for Sharp as follows: (in thousands) Balance Sheet Location September 30, 2021 December 31, 2020 Sharp Other Accrued Liabilities $ 6,094 $ 1,505 Financial Statements Presentation The following tables present information about the fair value and related gains and losses of our derivative contracts. We did not have any derivative contracts with a credit-risk-related contingency. The fair values of the derivative contracts recorded in the condensed consolidated balance sheets as of September 30, 2021 and December 31, 2020, are as follows: Derivative Assets Fair Value As Of (in thousands) Balance Sheet Location September 30, 2021 December 31, 2020 Derivatives designated as fair value hedges Propane put options Derivative assets, at fair value $ — $ 14 Derivatives designated as cash flow hedges Propane swap agreements Derivative assets, at fair value 12,185 3,255 Total asset derivatives $ 12,185 $ 3,269 Derivative Liabilities Fair Value As Of (in thousands) Balance Sheet Location September 30, 2021 December 31, 2020 Derivatives designated as fair value hedges Propane put options Derivative liabilities, at fair value $ — $ 23 Derivatives designated as cash flow hedges Propane swap agreements Derivative liabilities, at fair value 1,954 64 Interest rate swap agreements Derivative liabilities, at fair value 15 40 Total liability derivatives $ 1,969 $ 127 The effects of gains and losses from derivative instruments on the condensed consolidated financial statements are as follows: Amount of Gain (Loss) on Derivatives: Location of Gain For the Three Months Ended September 30, For the Nine Months Ended September 30, (in thousands) (Loss) on Derivatives 2021 2020 2021 2020 Derivatives designated as fair value hedges Propane put options Cost of sales $ — $ — $ (24) $ — Derivatives designated as cash flow hedges Propane swap agreements Cost of sales 681 116 4,183 1,581 Propane swap agreements Other comprehensive income 2,491 1,022 7,039 3,385 Interest rate swap agreements Interest expense 24 34 50 45 Interest rate swap agreements Other comprehensive income (loss) 19 37 24 (14) Total $ 3,215 $ 1,209 $ 11,272 $ 4,997

Fair Value of Financial Instrum

Fair Value of Financial Instruments	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Fair Value of Financial Instruments GAAP establishes a fair value hierarchy that prioritizes the inputs to valuation methods used to measure fair value. The three levels of the fair value hierarchy are the following: Fair Value Hierarchy Description of Fair Value Level Fair Value Technique Utilized Level 1 Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities Investments - equity securities - The fair values of these trading securities are recorded at fair value based on unadjusted quoted prices in active markets for identical securities. Investments - mutual funds and other - The fair values of these investments, comprised of money market and mutual funds, are recorded at fair value based on quoted net asset values of the shares. Level 2 Quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability Derivative assets and liabilities - The fair value of the propane put/call options, propane and interest rate swap agreements are measured using market transactions for similar assets and liabilities in either the listed or over-the-counter markets. Level 3 Prices or valuation techniques requiring inputs that are both significant to the fair value measurement and unobservable (i.e. supported by little or no market activity) Investments - guaranteed income fund - The fair values of these investments are recorded at the contract value, which approximates their fair value. Financial Assets and Liabilities Measured at Fair Value The following tables summarize our financial assets and liabilities that are measured at fair value on a recurring basis and the fair value measurements, by level, within the fair value hierarchy as of September 30, 2021 and December 31, 2020: Fair Value Measurements Using: As of September 30, 2021 Fair Value Quoted Prices in Significant Other Significant (in thousands) Assets: Investments—equity securities $ 23 $ 23 $ — $ — Investments—guaranteed income fund 2,016 — — 2,016 Investments—mutual funds and other 9,451 9,451 — — Total investments 11,490 9,474 — 2,016 Derivative assets 12,185 — 12,185 — Total assets $ 23,675 $ 9,474 $ 12,185 $ 2,016 Liabilities: Derivative liabilities $ 1,969 $ — $ 1,969 $ — Fair Value Measurements Using: As of December 31, 2020 Fair Value Quoted Prices in Significant Other Significant (in thousands) Assets: Investments—equity securities $ 21 $ 21 $ — $ — Investments—guaranteed income fund 2,156 — — 2,156 Investments—mutual funds and other 8,599 8,599 — — Total investments 10,776 8,620 — 2,156 Derivative assets 3,269 — 3,269 — Total assets $ 14,045 $ 8,620 $ 3,269 $ 2,156 Liabilities: Derivative liabilities $ 127 $ — $ 127 $ — The following table sets forth the summary of the changes in the fair value of Level 3 investments for the nine months ended September 30, 2021 and 2020: Nine months ended September 30, 2021 2020 (in thousands) Beginning Balance $ 2,156 $ 803 Purchases and adjustments 77 243 Transfers — 1,579 Distribution (241) (514) Investment income 24 18 Ending Balance $ 2,016 $ 2,129 Investment income from the Level 3 investments is reflected in other expense, (net) in the condensed consolidated statements of income. At September 30, 2021, there were no non-financial assets or liabilities required to be reported at fair value. We review our non-financial assets for impairment at least on an annual basis, as required. Other Financial Assets and Liabilities Financial assets with carrying values approximating fair value include cash and cash equivalents and accounts receivable. Financial liabilities with carrying values approximating fair value include accounts payable and other accrued liabilities and short-term debt. The fair value of cash and cash equivalents is measured using the comparable value in the active market and approximates its carrying value (Level 1 measurement). The fair value of short-term debt approximates the carrying value due to its near-term maturities and because interest rates approximate current market rates (Level 3 measurement). At September 30, 2021, long-term debt, which includes current maturities but excludes debt issuance costs, had a carrying value of approximately $522.5 million, compared to the estimated fair value of $561.9 million. At December 31, 2020, long-term debt, which includes the current maturities but excludes debt issuance costs, had a carrying value of approximately $523.0 million, compared to a fair value of approximately $548.5 million. The fair value was calculated using a discounted cash flow methodology that incorporates a market interest rate based on published corporate borrowing rates for debt instruments with similar terms and average maturities, and with adjustments for duration, optionality, and risk profile. The valuation technique used to estimate the fair value of long-term debt would be considered a Level 3 measurement.

Long-Term Debt

Long-Term Debt	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Long-Term Debt	Long-Term Debt Our outstanding long-term debt is shown below: September 30, December 31, (in thousands) 2021 2020 Uncollateralized senior notes: 5.93% note, due October 31, 2023 $ 7,500 $ 9,000 5.68% note, due June 30, 2026 14,500 17,400 6.43% note, due May 2, 2028 4,900 5,600 3.73% note, due December 16, 2028 16,000 16,000 3.88% note, due May 15, 2029 40,000 45,000 3.25% note, due April 30, 2032 70,000 70,000 3.48% note, due May 31, 2038 50,000 50,000 3.58% note, due November 30, 2038 50,000 50,000 3.98% note, due August 20, 2039 100,000 100,000 2.98% note, due December 20, 2034 70,000 70,000 3.00% note, due July 15, 2035 50,000 50,000 2.96% note, due August 15, 2035 40,000 40,000 Equipment security note 2.46% note, due September 29, 2031 9,590 — Less: debt issuance costs (825) (901) Total long-term debt 521,665 522,099 Less: current maturities (16,206) (13,600) Total long-term debt, net of current maturities $ 505,459 $ 508,499 Notes Purchase Agreement On August 25, 2021, we entered into a Note Purchase Agreement (“Note Agreement”) with multiple lenders to issue $50.0 million in uncollateralized senior notes. Under the Note Agreement, we will issue the senior notes on January 25, 2022 at a rate of 2.49 percent for a 15-year term. These senior notes, when issued, will have similar covenants and default provisions as the existing senior notes, and will have an annual principal payment beginning in the sixth year after the issuance. The proceeds received from the issuances of the senior notes will be used to reduce our short-term borrowings under our lines of credit and to fund capital expenditures. Equipment Security Note On September 24, 2021, we entered into an Equipment Financing Agreement with Banc of America Leasing & Capital, LLC to issue $9.6 million in sustainable financing to finance the purchase of equipment by our subsidiary, Marlin Gas Services. The equipment security note bears a 2.46 percent interest rate and has a term of ten years. Under the terms of the agreement, we granted a security interest in the equipment to the lender, to serve as collateral. Shelf Agreements We have entered into Shelf Agreements with Prudential, MetLife and NYL, whom are under no obligation to purchase any unsecured debt. The following table summarizes our Shelf Agreements at September 30, 2021: (in thousands) Total Borrowing Capacity Less: Amount of Debt Issued Less: Unfunded Commitments Remaining Borrowing Capacity Shelf Agreement Prudential Shelf Agreement (1) $ 370,000 $ (220,000) $ — $ 150,000 MetLife Shelf Agreement (1) 150,000 — — 150,000 NYL Shelf Agreement (1) 150,000 (140,000) — 10,000 Total Shelf Agreements as of September 30, 2021 $ 670,000 $ (360,000) $ — $ 310,000 (1) The Prudential, MetLife and NYL Shelf Agreements expire in April 2023, May 2023 and November 2021, respectively. The Uncollateralized Senior Notes, Shelf Agreements or Shelf Notes set forth certain business covenants to which we are subject when any note is outstanding, including covenants that limit or restrict our ability, and the ability of our subsidiaries, to incur indebtedness, or place or permit liens and encumbrances on any of our property or the property of our subsidiaries.

Short-Term Borrowings (Notes)

Short-Term Borrowings (Notes)	9 Months Ended
	Sep. 30, 2021
Short-Term Borrowing [Abstract]
Short-term Debt [Text Block]	16. Short-Term Borrowings We are authorized by our Board of Directors to borrow up to $400.0 million of short-term debt, as required. At September 30, 2021 and December 31, 2020, we had $192.0 million and $175.6 million, respectively, of short-term borrowings outstanding at a weighted average interest rate of 0.82 percent and 1.28 percent. Included in the September 30, 2021 balance, is $70.0 million in short-term debt for which we have entered into interest rate swap agreements. In August 2021, we amended and restated our Revolver into a multi-tranche facility totaling $400.0 million with multiple participating lenders. The two tranches of the facility consist of a $200.0 million 364-day short-term debt tranche and a $200.0 million five-year tranche, both of which have three (3) one-year extension options, which can be authorized by our Chief Financial Officer. We are eligible to establish the repayment term for individual borrowings under the five year tranche of the facility and to the extent that an individual loan under the revolver exceeded 12 months, the outstanding balance would be classified as a component of long-term debt. The availability of funds under the Revolver is subject to conditions specified in the credit agreement, all of which we currently satisfy. These conditions include our compliance with financial covenants and the continued accuracy of representations and warranties contained in these agreements. We are required by the financial covenants in the Revolver to maintain, at the end of each fiscal year, a funded indebtedness ratio of no greater than 65 percent. As of September 30, 2021, we are in compliance with this covenant. The 364-day tranche of the Revolver expires in August 2022 and the five-year tranche expires in August 2026 both are available to provide funds for our short-term cash needs to meet seasonal working capital requirements and to temporarily fund portions of our capital expenditures. Borrowings under both tranches of the Revolver are subject to a pricing grid, including the commitment fee and the interest rate charged. Our pricing is adjusted each quarter based upon a total indebtedness to total capitalization ratio. As of September 30, 2021, the pricing under the 364-day tranche of the Revolver does not include an unused commitment fee and maintains an interest rate of 0.70 percent over LIBOR. As of September 30, 2021, the pricing under the five-year tranche of the Revolver included an unused commitment fee of 0.09 percent and an interest rate of 0.95 percent over LIBOR. Our total available credit under the Revolver at September 30, 2021 was $203.4 million. As of September 30, 2021, we had issued $4.6 million in letters of credit to various counterparties under the syndicated Revolvers. These letters of credit are not included in the outstanding short-term borrowings and we do not anticipate that they will be drawn upon by the counterparties. The letters of credit reduce the available borrowings under our syndicated Revolver.

Leases Leases

Leases Leases	9 Months Ended
	Sep. 30, 2021
Lease Disclosure [Abstract]
Lessee, Operating Leases [Text Block]	Leases We have entered into lease arrangements for office space, land, equipment, pipeline facilities and warehouses. These lease arrangements enable us to better conduct business operations in the regions in which we operate. Office space is leased to provide adequate workspace for our employees in several locations throughout the Mid-Atlantic, Mid-West and in Florida. We lease land at various locations throughout our service territories to enable us to inject natural gas into underground storage and distribution systems, for bulk storage capacity, for our propane operations and for storage of equipment used in repairs and maintenance of our infrastructure. We lease natural gas compressors to ensure timely and reliable transportation of natural gas to our customers. Additionally, we lease a pipeline to deliver natural gas to an industrial customer in Polk County, Florida. We also lease warehouses to store equipment and materials used in repairs and maintenance for our businesses. Some of our leases are subject to annual changes in the Consumer Price Index (“CPI”). While lease liabilities are not re-measured as a result of changes to the CPI, changes to the CPI are treated as variable lease payments and recognized in the period in which the obligation for those payments was incurred. A 100-basis-point increase in CPI would not have resulted in material additional annual lease costs. Most of our leases include options to renew, with renewal terms that can extend the lease term from one to 25 years or more. The exercise of lease renewal options is at our sole discretion. The amounts disclosed in our consolidated balance sheet at September 30, 2021, pertaining to the right-of-use assets and lease liabilities, are measured based on our current expectations of exercising our available renewal options. Our existing leases are not subject to any restrictions or covenants that would preclude our ability to pay dividends, obtain financing or enter into additional leases. As of September 30, 2021, we have not entered into any leases, which have not yet commenced, that would entitle us to significant rights or create additional obligations. The following table presents information related to our total lease cost included in our consolidated statements of income: Three Months Ended Nine Months Ended September 30, September 30, ( in thousands) Classification 2021 2020 2021 2020 Operating lease cost (1) Operations expense $ 515 $ 627 $ 1,553 $ 1,882 (1) Includes short-term leases and variable lease costs, which are immaterial. The following table presents the balance and classifications of our right of use assets and lease liabilities included in our condensed consolidated balance sheet at September 30, 2021 and December 31, 2020: (in thousands) Balance sheet classification September 30, 2021 December 31, 2020 Assets Operating lease assets Operating lease right-of-use assets $ 9,602 $ 11,194 Liabilities Current Operating lease liabilities Other accrued liabilities $ 1,725 $ 1,747 Noncurrent Operating lease liabilities Operating lease - liabilities 8,380 9,872 Total lease liabilities $ 10,105 $ 11,619 The following table presents our weighted-average remaining lease terms and weighted-average discount rates for our operating and financing leases at September 30, 2021 and December 31, 2020: September 30, 2021 December 31, 2020 Weighted-average remaining lease term ( in years ) Operating leases 8.54 8.70 Weighted-average discount rate Operating leases 3.8 % 3.8 % The following table presents additional information related to cash paid for amounts included in the measurement of lease liabilities included in our condensed consolidated statements of cash flows as of September 30, 2021 and 2020: Nine Months Ended September 30, (in thousands) 2021 2020 Operating cash flows from operating leases $ 1,399 $ 1,435 The following table presents the future undiscounted maturities of our operating and financing leases at September 30, 2021 and for each of the next five years and thereafter: (in thousands) Operating Leases (1) Remainder of 2021 $ 597 2022 1,845 2023 1,762 2024 1,607 2025 1,387 2026 951 Thereafter 3,596 Total lease payments $ 11,745 Less: Interest (1,640) Present value of lease liabilities $ 10,105 (1) Operating lease payments include $2.1 million related to options to extend lease terms that are reasonably certain of being exercised.

Summary of Accounting Policies

Summary of Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
COVID-19 Effect [Policy Text Block]	Effects of COVID-19 In March 2020, the CDC declared a national emergency due to the rapidly growing outbreak of COVID-19. In response to this declaration and the rapid spread of COVID-19 within the United States, federal, state and local governments throughout the country imposed varying degrees of restrictions on social and commercial activity to promote social distancing in an effort to slow the spread of the illness. These restrictions significantly impacted economic conditions in the United States in 2020 and continued into 2021. Chesapeake Utilities is considered an “essential business,” which has allowed us to continue operational activities and construction projects while adhering to the social distancing restrictions that were in place. At this time, restrictions continue to be lifted as vaccines have become widely available in the United States. For example, the state of emergency in Florida was terminated in May 2021 followed by Delaware and Maryland in July 2021, resulting in reduced restrictions. The expiration of the states of emergency in our service territories has concluded our ability to defer incremental pandemic related costs for consideration through the applicable regulatory process. Despite these positive state orders and in light of the continued emergence and growing prevalence of the new variants of COVID-19, we continue to operate under our pandemic response plan, monitor developments affecting employees, customers, suppliers, and stockholders and take all precautions warranted to operate safely and to comply with the CDC, Occupational Safety and Health Administration, in order to protect our employees, customers and the communities we serve. Refer to Note 5 , Rates and Other Regulatory Activities , for further information on the regulated assets established as a result of the incremental expenses incurred associated with COVID-19.
Basis of Presentation	Basis of Presentation References in this document to the “Company,” “Chesapeake Utilities,” “we,” “us” and “our” are intended to mean Chesapeake Utilities Corporation, its divisions and/or its subsidiaries, as appropriate in the context of the disclosure. The accompanying unaudited condensed consolidated financial statements have been prepared in compliance with the rules and regulations of the SEC and GAAP. In accordance with these rules and regulations, certain information and disclosures normally required for audited financial statements have been condensed or omitted. These financial statements should be read in conjunction with the consolidated financial statements and notes thereto, included in our latest Annual Report on Form 10-K for the year ended December 31, 2020. In the opinion of management, these financial statements reflect all adjustments that are necessary for a fair presentation of our results of operations, financial position and cash flows for the interim periods presented. Where necessary to improve comparability, prior period amounts have been changed to conform to current period presentation. Due to the seasonality of our business, results for interim periods are not necessarily indicative of results for the entire fiscal year. Revenue and earnings are typically greater during the first and fourth quarters, when consumption of energy is highest due to colder temperatures.
FASB Statements and Other Authoritative Pronouncements	FASB Statements and Other Authoritative Pronouncements There are no new accounting pronouncements issued that are applicable to us.

Calculation of Earnings Per S_2

Calculation of Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Calculation of Basic and Diluted Earnings Per Share	Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands, except shares and per share data) Calculation of Basic Earnings Per Share: Income from Continuing Operations $ 12,484 $ 9,280 $ 60,771 $ 48,981 Income/(Loss) from Discontinued Operations (9) (19) (17) 165 Net Income $ 12,475 $ 9,261 $ 60,754 $ 49,146 Weighted average shares outstanding 17,582,115 16,533,748 17,538,461 16,466,106 Basic Earnings Per Share from Continuing Operations $ 0.71 $ 0.56 $ 3.46 $ 2.97 Basic Earnings Per Share from Discontinued Operations — — — 0.01 Basic Earnings Per Share $ 0.71 $ 0.56 $ 3.46 $ 2.98 Calculation of Diluted Earnings Per Share: Reconciliation of Denominator: Weighted shares outstanding—Basic 17,582,115 16,533,748 17,538,461 16,466,106 Effect of dilutive securities—Share-based compensation 77,528 59,094 71,697 57,094 Adjusted denominator—Diluted 17,659,643 16,592,842 17,610,158 16,523,200 Diluted Earnings Per Share from Continuing Operations $ 0.71 $ 0.56 $ 3.45 $ 2.96 Diluted Earnings Per Share from Discontinued Operations — — — 0.01 Diluted Earnings Per Share $ 0.71 $ 0.56 $ 3.45 $ 2.97

Revenue Recognition (Tables)

Revenue Recognition (Tables)	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue [Table Text Block]	The following table displays our revenue from continuing operations by major source based on product and service type for the three months ended September 30, 2021 and 2020: Three months ended September 30, 2021 Three months ended September 30, 2020 (in thousands) Regulated Energy Unregulated Energy Other and Eliminations Total Regulated Energy Unregulated Energy Other and Eliminations Total Energy distribution Delaware natural gas division $ 7,849 $ — $ — $ 7,849 $ 7,243 $ — $ — $ 7,243 Florida natural gas division 8,015 — — 8,015 7,309 — — 7,309 FPU electric distribution 23,121 — — 23,121 29,051 — — 29,051 FPU natural gas distribution 22,012 — — 22,012 19,935 — — 19,935 Maryland natural gas division 2,432 — — 2,432 2,824 — — 2,824 Sandpiper natural gas/propane operations 3,553 — — 3,553 3,290 — — 3,290 Elkton Gas 915 — — 915 623 — — 623 Total energy distribution 67,897 — — 67,897 70,275 — — 70,275 Energy transmission Aspire Energy — 5,255 — 5,255 — 3,449 — 3,449 Aspire Energy Express 47 — — 47 — — — — Eastern Shore 18,558 — — 18,558 18,389 — — 18,389 Peninsula Pipeline 6,776 — — 6,776 6,433 — — 6,433 Total energy transmission 25,381 5,255 — 30,636 24,822 3,449 — 28,271 Energy generation Eight Flags — 4,583 — 4,583 — 3,882 — 3,882 Propane operations Propane delivery operations — 20,680 — 20,680 — 13,710 — 13,710 Energy delivery services Marlin Gas Services — 1,678 — 1,678 — 1,708 — 1,708 Other and eliminations Eliminations (12,882) (87) (5,302) (18,271) (12,335) (35) (4,188) (16,558) Other — — 132 132 — — 131 131 Total other and eliminations (12,882) (87) (5,170) (18,139) (12,335) (35) (4,057) (16,427) Total operating revenues (1) $ 80,396 $ 32,109 $ (5,170) $ 107,335 $ 82,762 $ 22,714 $ (4,057) $ 101,419 (1) Total operating revenues for the three months ended September 30, 2021, include other revenue (revenues from sources other than contracts with customers) of $0.1 million for both Regulated and Unregulated Energy segments, respectively, and $0.2 million and $0.05 million for our Regulated and Unregulated Energy segments, respectively, for the three months ended September 30, 2020. The sources of other revenues include revenue from alternative revenue programs related to revenue normalization for the Maryland division and Sandpiper Energy and late fees. The following table displays our revenue from continuing operations by major source based on product and service type for the nine months ended September 30, 2021 and 2020: Nine months ended September 30, 2021 Nine months ended September 30, 2020 (in thousands) Regulated Energy Unregulated Energy Other and Eliminations Total Regulated Energy Unregulated Energy Other and Eliminations Total Energy distribution Delaware natural gas division $ 51,188 $ — $ — $ 51,188 $ 45,568 $ — $ — $ 45,568 Florida natural gas division 25,417 — — 25,417 23,018 — — 23,018 FPU electric distribution 60,569 — — 60,569 58,972 — — 58,972 FPU natural gas distribution 72,032 — — 72,032 64,877 — — 64,877 Maryland natural gas division 16,122 — — 16,122 15,941 — — 15,941 Sandpiper natural gas/propane operations 15,438 — — 15,438 12,440 — — 12,440 Elkton Gas 4,745 — — 4,745 623 — — 623 Total energy distribution 245,511 — — 245,511 221,439 — — 221,439 Energy transmission Aspire Energy — 23,738 — 23,738 — 17,784 — 17,784 Aspire Energy Express 140 — — 140 — — — — Eastern Shore 57,147 — — 57,147 55,944 — — 55,944 Peninsula Pipeline 19,853 — — 19,853 16,618 — — 16,618 Total energy transmission 77,140 23,738 — 100,878 72,562 17,784 — 90,346 Energy generation Eight Flags — 13,086 — 13,086 — 11,898 — 11,898 Propane operations Propane delivery operations — 99,041 — 99,041 — 69,593 — 69,593 Energy delivery services Marlin Gas Services — 6,019 — 6,019 — 5,266 — 5,266 Other and eliminations Eliminations (40,148) (242) (14,937) (55,327) (34,766) (75) (12,937) (47,778) Other — 396 396 — — 396 396 Total other and eliminations (40,148) (242) (14,541) (54,931) (34,766) (75) (12,541) (47,382) Total operating revenues (1) $ 282,503 $ 141,642 $ (14,541) $ 409,604 $ 259,235 $ 104,466 $ (12,541) $ 351,160 (1) Total operating revenues for the nine months ended September 30, 2021, include other revenue (revenues from sources other than contracts with customers) of $(0.1) million and $0.3 million for our Regulated and Unregulated Energy segments, respectively, and $1.0 million and $0.2 million for our Regulated and Unregulated Energy segments, respectively, for the nine months ended September 30, 2020. The sources of other revenues include revenue from alternative revenue programs related to revenue normalization for the Maryland division and Sandpiper Energy and late fees.
Contract with Customer, Asset and Liability [Table Text Block]	The balances of our trade receivables, contract assets, and contract liabilities as of September 30, 2021 and December 31, 2020 were as follows: Trade Receivables Contract Assets (Current) Contract Assets (Non-current) Contract Liabilities (Current) (in thousands) Balance at 12/31/2020 $ 55,600 $ 18 $ 4,816 $ 644 Balance at 9/30/2021 40,683 18 5,011 874 Increase (decrease) $ (14,917) $ — $ 195 $ 230
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block]	Revenue for these businesses for the remaining performance obligations, at September 30, 2021, are expected to be recognized as follows: (in thousands) 2021 2022 2023 2024 2025 2026 2027 and thereafter Eastern Shore and Peninsula Pipeline $ 9,471 $ 32,796 $ 25,205 $ 22,975 $ 22,102 $ 21,023 $ 179,728 Natural gas distribution operations 1,752 6,620 6,044 5,811 5,271 5,064 33,448 FPU electric distribution 163 652 652 652 275 275 550 Total revenue contracts with remaining performance obligations $ 11,386 $ 40,068 $ 31,901 $ 29,438 $ 27,648 $ 26,362 $ 213,726

Rates and Other Regulatory Ac_2

Rates and Other Regulatory Activities Rates and Regulatory Activities (Tables)	9 Months Ended
	Sep. 30, 2021
Rates and Regulatory Activities [Abstract]
Summary of Effects of Federal Tax Reform on Regulated Businesses [Table Text Block]	The following table summarizes the regulatory liabilities related to accumulated deferred taxes ("ADIT") associated with TCJA for our regulated businesses as of September 30, 2021 and December 31, 2020: Amount (in thousands) Operation and Regulatory Jurisdiction September 30, 2021 December 31, 2020 Status Eastern Shore (FERC) $34,190 $34,190 Will be addressed in Eastern Shore's next rate case filing. Delaware Division (Delaware PSC) $12,626 $12,728 PSC approved amortization of ADIT in January 2019. Maryland Division (Maryland PSC) $3,873 $3,970 PSC approved amortization of ADIT in May 2018. Sandpiper Energy (Maryland PSC) $3,670 $3,713 PSC approved amortization of ADIT in May 2018. Chesapeake Florida Gas Division/Central Florida Gas (Florida PSC) $8,070 $8,184 PSC issued order authorizing amortization and retention of net ADIT liability by the Company in February 2019. FPU Natural Gas (excludes Fort Meade and Indiantown) (Florida PSC) $19,132 $19,257 Same treatment on a net basis as Chesapeake Florida Gas Division (above). FPU Fort Meade and Indiantown Divisions $274 $309 Same treatment on a net basis as Chesapeake Florida Gas Division (above). FPU Electric (Florida PSC) $5,299 $6,694 In January 2019, PSC issued order approving amortization of ADIT through purchased power cost recovery, storm reserve and rates. Elkton Gas (Maryland PSC) $1,124 $1,124 PSC approved amortization of ADIT in March 2018.

Environmental Commitments and_2

Environmental Commitments and Contingencies Summary of Environmental Liabilities (Tables)	9 Months Ended
	Sep. 30, 2021
Environmental Commitments and Contingencies [Abstract]
Environmental Remedies [Table Text Block]	Status Estimated Clean-Up Costs Remedial actions approved by the Florida Department of Environmental Protection have been implemented on the east parcel of the site. Similar remedial actions have been initiated on the site's west parcel, and construction of active remedial systems are expected be completed in 2022. Between $3.3 million to $14.2 million, including costs associated with the relocation of FPU’s operations at this site, and any potential costs associated with future redevelopment of the properties.

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Schedule of Segment Reporting Information by Segment	The following table presents financial information about our reportable segments: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Operating Revenues, Unaffiliated Customers Regulated Energy $ 79,892 $ 82,297 $ 280,987 $ 257,810 Unregulated Energy 27,443 19,122 128,617 93,350 Total operating revenues, unaffiliated customers $ 107,335 $ 101,419 $ 409,604 $ 351,160 Intersegment Revenues (1) Regulated Energy $ 504 $ 465 $ 1,516 $ 1,425 Unregulated Energy 4,666 3,592 13,024 11,116 Other businesses 132 131 397 396 Total intersegment revenues $ 5,302 $ 4,188 $ 14,937 $ 12,937 Operating Income Regulated Energy $ 23,538 $ 20,482 $ 79,210 $ 66,376 Unregulated Energy (2,883) (3,092) 15,777 11,050 Other businesses and eliminations (542) 16 (699) 92 Operating income 20,113 17,406 94,288 77,518 Other income (expense), net 339 (40) 2,180 2,997 Interest charges 4,975 4,584 15,134 15,452 Income from Continuing Operations before Income Taxes 15,477 12,782 81,334 65,063 Income Taxes on Continuing Operations 2,993 3,502 20,563 16,082 Income from Continuing Operations 12,484 9,280 60,771 48,981 Income (Loss) from Discontinued Operations, Net of Tax (9) (19) (17) 165 Net Income $ 12,475 $ 9,261 $ 60,754 $ 49,146 (1) All significant intersegment revenues are billed at market rates and have been eliminated from consolidated operating revenues. (in thousands) September 30, 2021 December 31, 2020 Identifiable Assets Regulated Energy segment $ 1,592,950 $ 1,547,619 Unregulated Energy segment 381,642 347,665 Other businesses and eliminations 47,236 37,203 Total identifiable assets $ 2,021,828 $ 1,932,487

Stockholder's Equity - Accumu_2

Stockholder's Equity - Accumulated Other Comprehensive Income (Loss) (Tables)	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Changes in Accumulated Other Comprehensive Loss	Defined Benefit Commodity Interest Rate Pension and Contracts Swap Postretirement Cash Flow Cash Flow Plan Items Hedges Hedges Total (in thousands) As of December 31, 2020 $ (5,146) $ 2,309 $ (28) $ (2,865) Other comprehensive income before reclassifications — 8,121 55 8,176 Amounts reclassified from accumulated other comprehensive income (loss) 192 (3,027) (37) (2,872) Net current-period other comprehensive income 192 5,094 18 5,304 As of September 30, 2021 $ (4,954) $ 7,403 $ (10) $ 2,439 (in thousands) As of December 31, 2019 $ (4,933) $ (1,334) $ — $ (6,267) Other comprehensive income before reclassifications — 3,594 23 3,617 Amounts reclassified from accumulated other comprehensive income/(loss) 198 (1,144) (33) (979) Net prior-period other comprehensive income/(loss) 198 2,450 (10) 2,638 As of September 30, 2020 $ (4,735) $ 1,116 $ (10) $ (3,629)
Reclassifications out of Accumulated Other Comprehensive Income (Loss)	The following table presents amounts reclassified out of accumulated other comprehensive income (loss) for the three and nine months ended September 30, 2021 and 2020. Deferred gains or losses for our commodity contracts and interest rate swap cash flow hedges are recognized in earnings upon settlement. Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Amortization of defined benefit pension and postretirement plan items: Prior service credit (1) $ 19 $ 19 $ 57 $ 57 Net loss (1) (106) (108) (317) (323) Total before income taxes (87) (89) (260) (266) Income tax benefit 23 23 68 68 Net of tax $ (64) $ (66) $ (192) $ (198) Gains on commodity contracts cash flow hedges: Propane swap agreements (2) $ 681 $ 116 $ 4,183 $ 1,581 Income tax expense (188) (32) (1,156) (437) Net of tax $ 493 $ 84 $ 3,027 $ 1,144 Gains on interest rate swap cash flow hedges: Interest rate swap agreements $ 24 $ 34 $ 50 $ 45 Income tax expense (6) (9) (13) (12) Net of tax $ 18 $ 25 $ 37 $ 33 Total reclassifications for the period $ 447 $ 43 $ 2,872 $ 979 (1) These amounts are included in the computation of net periodic costs (benefits). See Note 10 , Employee Benefit Plans , for additional details. (2) These amounts are included in the effects of gains and losses from derivative instruments. See Note 13, Derivative Instruments , for additional details.

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	9 Months Ended
	Sep. 30, 2021
Retirement Benefits [Abstract]
Schedule of Net Benefit Costs [Table Text Block]	Net periodic benefit costs for our pension and post-retirement benefits plans for the three and nine months ended September 30, 2021 and 2020 are set forth in the following tables: Chesapeake FPU Chesapeake SERP Chesapeake FPU For the Three Months Ended September 30, 2021 2020 2021 2020 2021 2020 2021 2020 2021 2020 (in thousands) Interest cost $ 34 $ 46 $ 429 $ 518 $ 12 $ 16 $ 6 $ 8 $ 6 $ 10 Expected return on plan assets (40) (42) (830) (745) — — — — — — Amortization of prior service credit — — — — — — (19) (19) — — Amortization of net (gain) loss 60 65 155 135 7 5 10 12 (2) — Net periodic cost (benefit) 54 69 (246) (92) 19 21 (3) 1 4 10 Amortization of pre-merger regulatory asset — — — — — — — — — 2 Total periodic cost (benefit) $ 54 $ 69 $ (246) $ (92) $ 19 $ 21 $ (3) $ 1 $ 4 $ 12 Chesapeake FPU Chesapeake SERP Chesapeake FPU For the Nine Months Ended September 30, 2021 2020 2021 2020 2021 2020 2021 2020 2021 2020 (in thousands) Interest cost $ 102 $ 138 $ 1,287 $ 1,554 $ 36 $ 48 $ 18 $ 24 $ 18 $ 30 Expected return on plan assets (120) (126) (2,490) (2,235) — — — — — — Amortization of prior service credit — — — — — — (57) (57) — — Amortization of net (gain) loss 180 195 465 405 21 15 30 36 (6) — Net periodic cost (benefit) 162 207 (738) (276) 57 63 (9) 3 12 30 Amortization of pre-merger regulatory asset — — — — — — — — — 6 Total periodic cost (benefit) $ 162 $ 207 $ (738) $ (276) $ 57 $ 63 $ (9) $ 3 $ 12 $ 36
Amounts Included in Regulatory asset and AOCI [Table Text Block]	The following tables present the amounts included in the regulatory asset and accumulated other comprehensive income that were recognized as components of net periodic benefit cost during the three and nine months ended September 30, 2021 and 2020: For the Three Months Ended September 30, 2021 Chesapeake FPU Chesapeake SERP Chesapeake FPU Total (in thousands) Prior service credit $ — $ — $ — $ (19) $ — $ (19) Net loss 60 155 7 10 (2) 230 Total recognized in net periodic benefit cost 60 155 7 (9) (2) 211 Recognized from accumulated other comprehensive (income)/loss (1) 60 29 7 (9) — 87 Recognized from regulatory asset — 126 — — (2) 124 Total $ 60 $ 155 $ 7 $ (9) $ (2) $ 211 For the Three Months Ended September 30, 2020 Chesapeake FPU Chesapeake SERP Chesapeake FPU Total (in thousands) Prior service credit $ — $ — $ — $ (19) $ — $ (19) Net loss 65 135 5 12 — 217 Total recognized in net periodic benefit cost 65 135 5 (7) — 198 Recognized from accumulated other comprehensive (income)/loss (1) 65 26 5 (7) — 89 Recognized from regulatory asset — 109 — — — 109 Total $ 65 $ 135 $ 5 $ (7) $ — $ 198 For the Nine Months Ended September 30, 2021 Chesapeake FPU Chesapeake SERP Chesapeake FPU Total (in thousands) Prior service credit $ — $ — $ — $ (57) $ — $ (57) Net loss 180 465 21 30 (6) 690 Total recognized in net periodic benefit cost 180 465 21 (27) (6) 633 Recognized from accumulated other comprehensive (income)/loss (1) 180 87 21 (27) (1) 260 Recognized from regulatory asset — 378 — — (5) 373 Total $ 180 $ 465 $ 21 $ (27) $ (6) $ 633 For the Nine Months Ended September 30, 2020 Chesapeake FPU Chesapeake SERP Chesapeake FPU Total (in thousands) Prior service credit $ — $ — $ — $ (57) $ — $ (57) Net loss 195 405 15 36 — 651 Total recognized in net periodic benefit cost 195 405 15 (21) — 594 Recognized from accumulated other comprehensive (income)/loss (1) 195 78 15 (21) — 267 Recognized from regulatory asset — 327 — — — 327 Total $ 195 $ 405 $ 15 $ (21) $ — $ 594 (1) See Note 9 , Stockholders' Equity

Investments (Tables)

Investments (Tables)	9 Months Ended
	Sep. 30, 2021
Investments, Debt and Equity Securities [Abstract]
Investments schedule [Table Text Block]	The investment balances at September 30, 2021 and December 31, 2020, consisted of the following: (in thousands) September 30, December 31, Rabbi trust (associated with the Non-Qualified Deferred Compensation Plan) $ 11,467 $ 10,755 Investments in equity securities 23 21 Total $ 11,490 $ 10,776

Share-Based Compensation (Table

Share-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2021
Shares awarded to non-employee directors [Line Items]
Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan	The table below presents the amounts included in net income related to share-based compensation expense for the three and nine months ended September 30, 2021 and 2020: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Awards to non-employee directors $ 201 $ 188 $ 581 $ 545 Awards to key employees 1,105 1,144 4,039 3,109 Total compensation expense 1,306 1,332 4,620 3,654 Less: tax benefit (339) (348) (1,200) (955) Share-based compensation amounts included in net income $ 967 $ 984 $ 3,420 $ 2,699
Award to key employees [Member]
Shares awarded to non-employee directors [Line Items]
Schedule of Share-based Compensation, Activity	The table below presents the summary of the stock activity for awards to key employees for the nine months ended September 30, 2021: Number of Shares Weighted Average Outstanding—December 31, 2020 186,878 $ 87.06 Granted 68,562 $ 102.73 Vested (53,147) $ 76.31 Expired (852) $ 74.85 Forfeited (5,384) $ 93.39 Outstanding—September 30, 2021 196,057 $ 94.15

Derivative Instruments (Tables)

Derivative Instruments (Tables)	9 Months Ended
	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments [Table Text Block]	As of September 30, 2021, the volume of our commodity derivative contracts were as follows: Business unit Commodity Contract Type Quantity hedged (in millions) Designation Longest Expiration date of hedge Sharp Propane (gallons) Purchases 23.4 Cash flows hedges June 2024 Sharp Propane (gallons) Sales 5.0 Cash flows hedges March 2022
Schedule of Due to (from) Broker-Dealers and Clearing Organizations [Table Text Block]	(in thousands) Balance Sheet Location September 30, 2021 December 31, 2020 Sharp Other Accrued Liabilities $ 6,094 $ 1,505
Fair Values of Derivative Contracts Recorded in Condensed Consolidated Balance Sheet	September 30, 2021 and December 31, 2020, are as follows: Derivative Assets Fair Value As Of (in thousands) Balance Sheet Location September 30, 2021 December 31, 2020 Derivatives designated as fair value hedges Propane put options Derivative assets, at fair value $ — $ 14 Derivatives designated as cash flow hedges Propane swap agreements Derivative assets, at fair value 12,185 3,255 Total asset derivatives $ 12,185 $ 3,269 Derivative Liabilities Fair Value As Of (in thousands) Balance Sheet Location September 30, 2021 December 31, 2020 Derivatives designated as fair value hedges Propane put options Derivative liabilities, at fair value $ — $ 23 Derivatives designated as cash flow hedges Propane swap agreements Derivative liabilities, at fair value 1,954 64 Interest rate swap agreements Derivative liabilities, at fair value 15 40 Total liability derivatives $ 1,969 $ 127
Effects of Gains and Losses from Derivative Instruments on Condensed Consolidated Financial Statements	The effects of gains and losses from derivative instruments on the condensed consolidated financial statements are as follows: Amount of Gain (Loss) on Derivatives: Location of Gain For the Three Months Ended September 30, For the Nine Months Ended September 30, (in thousands) (Loss) on Derivatives 2021 2020 2021 2020 Derivatives designated as fair value hedges Propane put options Cost of sales $ — $ — $ (24) $ — Derivatives designated as cash flow hedges Propane swap agreements Cost of sales 681 116 4,183 1,581 Propane swap agreements Other comprehensive income 2,491 1,022 7,039 3,385 Interest rate swap agreements Interest expense 24 34 50 45 Interest rate swap agreements Other comprehensive income (loss) 19 37 24 (14) Total $ 3,215 $ 1,209 $ 11,272 $ 4,997

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Financial Assets and Liabilities Measured at Fair Value on Recurring Basis	The following tables summarize our financial assets and liabilities that are measured at fair value on a recurring basis and the fair value measurements, by level, within the fair value hierarchy as of September 30, 2021 and December 31, 2020: Fair Value Measurements Using: As of September 30, 2021 Fair Value Quoted Prices in Significant Other Significant (in thousands) Assets: Investments—equity securities $ 23 $ 23 $ — $ — Investments—guaranteed income fund 2,016 — — 2,016 Investments—mutual funds and other 9,451 9,451 — — Total investments 11,490 9,474 — 2,016 Derivative assets 12,185 — 12,185 — Total assets $ 23,675 $ 9,474 $ 12,185 $ 2,016 Liabilities: Derivative liabilities $ 1,969 $ — $ 1,969 $ — Fair Value Measurements Using: As of December 31, 2020 Fair Value Quoted Prices in Significant Other Significant (in thousands) Assets: Investments—equity securities $ 21 $ 21 $ — $ — Investments—guaranteed income fund 2,156 — — 2,156 Investments—mutual funds and other 8,599 8,599 — — Total investments 10,776 8,620 — 2,156 Derivative assets 3,269 — 3,269 — Total assets $ 14,045 $ 8,620 $ 3,269 $ 2,156 Liabilities: Derivative liabilities $ 127 $ — $ 127 $ —
Summary of Changes in Fair Value of Investments	The following table sets forth the summary of the changes in the fair value of Level 3 investments for the nine months ended September 30, 2021 and 2020: Nine months ended September 30, 2021 2020 (in thousands) Beginning Balance $ 2,156 $ 803 Purchases and adjustments 77 243 Transfers — 1,579 Distribution (241) (514) Investment income 24 18 Ending Balance $ 2,016 $ 2,129

Long-Term Debt (Tables)

Long-Term Debt (Tables)	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Outstanding Long-Term Debt	Our outstanding long-term debt is shown below: September 30, December 31, (in thousands) 2021 2020 Uncollateralized senior notes: 5.93% note, due October 31, 2023 $ 7,500 $ 9,000 5.68% note, due June 30, 2026 14,500 17,400 6.43% note, due May 2, 2028 4,900 5,600 3.73% note, due December 16, 2028 16,000 16,000 3.88% note, due May 15, 2029 40,000 45,000 3.25% note, due April 30, 2032 70,000 70,000 3.48% note, due May 31, 2038 50,000 50,000 3.58% note, due November 30, 2038 50,000 50,000 3.98% note, due August 20, 2039 100,000 100,000 2.98% note, due December 20, 2034 70,000 70,000 3.00% note, due July 15, 2035 50,000 50,000 2.96% note, due August 15, 2035 40,000 40,000 Equipment security note 2.46% note, due September 29, 2031 9,590 — Less: debt issuance costs (825) (901) Total long-term debt 521,665 522,099 Less: current maturities (16,206) (13,600) Total long-term debt, net of current maturities $ 505,459 $ 508,499
Schedule of Line of Credit Facilities [Line Items]
Schedule of Line of Credit Facilities [Table Text Block]	(in thousands) Total Borrowing Capacity Less: Amount of Debt Issued Less: Unfunded Commitments Remaining Borrowing Capacity Shelf Agreement Prudential Shelf Agreement (1) $ 370,000 $ (220,000) $ — $ 150,000 MetLife Shelf Agreement (1) 150,000 — — 150,000 NYL Shelf Agreement (1) 150,000 (140,000) — 10,000 Total Shelf Agreements as of September 30, 2021 $ 670,000 $ (360,000) $ — $ 310,000

Leases Leases (Tables)

Leases Leases (Tables)	9 Months Ended
	Sep. 30, 2021
Lease Disclosure [Abstract]
Lease, Cost [Table Text Block]	Three Months Ended Nine Months Ended September 30, September 30, ( in thousands) Classification 2021 2020 2021 2020 Operating lease cost (1) Operations expense $ 515 $ 627 $ 1,553 $ 1,882
Schedule of Leases Reported on Consolidated Statement of Financial Position [Table Text Block]	The following table presents the balance and classifications of our right of use assets and lease liabilities included in our condensed consolidated balance sheet at September 30, 2021 and December 31, 2020: (in thousands) Balance sheet classification September 30, 2021 December 31, 2020 Assets Operating lease assets Operating lease right-of-use assets $ 9,602 $ 11,194 Liabilities Current Operating lease liabilities Other accrued liabilities $ 1,725 $ 1,747 Noncurrent Operating lease liabilities Operating lease - liabilities 8,380 9,872 Total lease liabilities $ 10,105 $ 11,619
Leases, Weighted Average Remaining Lease Term [Table Text Block]	The following table presents our weighted-average remaining lease terms and weighted-average discount rates for our operating and financing leases at September 30, 2021 and December 31, 2020: September 30, 2021 December 31, 2020 Weighted-average remaining lease term ( in years ) Operating leases 8.54 8.70 Weighted-average discount rate Operating leases 3.8 % 3.8 %
Lease, Cash Flow [Table Text Block]	The following table presents additional information related to cash paid for amounts included in the measurement of lease liabilities included in our condensed consolidated statements of cash flows as of September 30, 2021 and 2020: Nine Months Ended September 30, (in thousands) 2021 2020 Operating cash flows from operating leases $ 1,399 $ 1,435
Schedule of Maturities of Leases [Table Text Block]	The following table presents the future undiscounted maturities of our operating and financing leases at September 30, 2021 and for each of the next five years and thereafter: (in thousands) Operating Leases (1) Remainder of 2021 $ 597 2022 1,845 2023 1,762 2024 1,607 2025 1,387 2026 951 Thereafter 3,596 Total lease payments $ 11,745 Less: Interest (1,640) Present value of lease liabilities $ 10,105 (1) Operating lease payments include $2.1 million related to options to extend lease terms that are reasonably certain of being exercised.

Calculation of Earnings Per S_3

Calculation of Earnings Per Share - Calculation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share [Abstract]
Income (Loss) from Continuing Operations, Per Basic Share	$ 0.71	$ 0.56	$ 3.46	$ 2.97
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share	$ 0	$ 0	$ 0	$ 0.01
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent	$ 12,484	$ 9,280	$ 60,771	$ 48,981
Calculation of Basic Earnings Per Share:
Net Income	$ 12,475	$ 9,261	$ 60,754	$ 49,146
Weighted shares outstanding (shares)	17,582,115	16,533,748	17,538,461	16,466,106
Basic Earnings Per Share (in dollars per share)	$ 0.71	$ 0.56	$ 3.46	$ 2.98
Reconciliation of Numerator:
Net Income	$ 12,475	$ 9,261	$ 60,754	$ 49,146
Reconciliation of Denominator:
Weighted shares outstanding - Basic (shares)	17,582,115	16,533,748	17,538,461	16,466,106
Effect of dilutive securities:
Share-based compensation (shares)	77,528	59,094	71,697	57,094
Adjusted denominator-Diluted (shares)	17,659,643	16,592,842	17,610,158	16,523,200
Income (Loss) from Continuing Operations, Per Diluted Share	$ 0.71	$ 0.56	$ 3.45	$ 2.96
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share	0	0	0	0.01
Diluted Earnings Per Share (in dollars per share)	$ 0.71	$ 0.56	$ 3.45	$ 2.97
Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, Net of Tax	$ (9)	$ (19)	$ (17)	$ 165
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent	12,484	9,280	60,771	48,981
Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, Net of Tax	(9)	(19)	(17)	165
Net Income	$ 12,475	$ 9,261	$ 60,754	$ 49,146
Basic (shares)	17,582,115	16,533,748	17,538,461	16,466,106
Income (Loss) from Continuing Operations, Per Basic Share	$ 0.71	$ 0.56	$ 3.46	$ 2.97
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share	0	0	0	0.01
Basic (in dollars per share)	$ 0.71	$ 0.56	$ 3.46	$ 2.98
Share-based compensation (shares)	77,528	59,094	71,697	57,094
Diluted (shares)	17,659,643	16,592,842	17,610,158	16,523,200
Income (Loss) from Continuing Operations, Per Diluted Share	$ 0.71	$ 0.56	$ 3.45	$ 2.96
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share	0	0	0	0.01
Diluted (in dollars per share)	$ 0.71	$ 0.56	$ 3.45	$ 2.97
Retained Earnings [Member]
Earnings Per Share [Abstract]
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent	$ 12,484	$ 9,280	$ 60,771	$ 48,981
Calculation of Basic Earnings Per Share:
Net Income	12,475	9,261	60,754	49,146
Reconciliation of Numerator:
Net Income	12,475	9,261	60,754	49,146
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent	12,484	9,280	60,771	48,981
Net Income	$ 12,475	$ 9,261	$ 60,754	$ 49,146

Acquisitions and Divestitures_2

Acquisitions and Divestitures (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)Dekatherm	Sep. 30, 2020USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues	$ 107,335	$ 101,419	$ 409,604	$ 351,160
Operating Income (Loss)	20,113	17,406	94,288	77,518
Unregulated Energy [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Operating Income (Loss)	(2,883)	(3,092)	15,777	11,050
Regulated Energy [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Operating Income (Loss)	23,538	$ 20,482	79,210	$ 66,376
Elkton Gas [Member] | Regulated Energy [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	15,900		15,900
Revenues	900		4,700
Operating Income (Loss)	(100)		$ 700
Number of customers acquired through acquisition			7,000
Business Combination, Consideration Transferred			$ 15,600
Business Combination, Working Capital	600		600
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	600		600
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	2,600		2,600
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	4,300		4,300
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Regulatory Liabilities			2,600
Western Natural Gas [Member] | Unregulated Energy [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	3,500		3,500
Revenues	500		1,900
Operating Income (Loss)	100		400
Business Combination, Consideration Transferred			6,700
Business Combination, Working Capital	300		300
Business Combination, Contingent Consideration, Liability	300		300
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	1,800		1,800
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets	$ 1,400		$ 1,400
Escambia Meter | Regulated Energy [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional Firm Natural Gas Transportation Deliverability | Dekatherm			530,000

Revenue Recognition Additional

Revenue Recognition Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Contract with Customer, Liability, Revenue Recognized	$ 200	$ 800

Revenue Recognition Disegragati

Revenue Recognition Disegragation of Revenue (Details) - USD ($)	3 Months Ended				9 Months Ended
	Sep. 30, 2021		Sep. 30, 2020		Sep. 30, 2021		Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Revenues	$ 107,335,000		$ 101,419,000		$ 409,604,000		$ 351,160,000
Revenue from Contract with Customer, Excluding Assessed Tax	107,335,000	[1]	101,419,000	[1]	409,604,000	[2]	351,160,000	[2]
Regulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	80,396,000	[1]	82,762,000	[1]	282,503,000	[2]	259,235,000	[2]
Unregulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	32,109,000	[1]	22,714,000	[1]	141,642,000	[2]	104,466,000	[2]
Other Segments And Intersegments Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	(5,170,000)		(4,057,000)		(14,541,000)		(12,541,000)
Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	(5,170,000)	[1]	(4,057,000)	[1]	(14,541,000)	[2]	(12,541,000)	[2]
Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	(18,139,000)		(16,427,000)		(54,931,000)		(47,382,000)
Eliminations [Member] | Regulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	(12,882,000)		(12,335,000)		(40,148,000)		(34,766,000)
Other [Member] | Regulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenues	100,000		200,000		(100,000)		1,000,000
Other [Member] | Unregulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenues			50,000		300,000		200,000
Revenue from Contract with Customer, Excluding Assessed Tax	(87,000)		(35,000)		(242,000)		(75,000)
Energy Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	67,897,000		70,275,000		245,511,000		221,439,000
Energy Distribution [Member] | Regulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	67,897,000		70,275,000		245,511,000		221,439,000
Energy Distribution [Member] | Delaware natural gas division [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	7,849,000		7,243,000		51,188,000		45,568,000
Energy Distribution [Member] | Delaware natural gas division [Member] | Regulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	7,849,000		7,243,000		51,188,000		45,568,000
Energy Distribution [Member] | Central Florida Gas Division [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	8,015,000		7,309,000		25,417,000		23,018,000
Energy Distribution [Member] | Central Florida Gas Division [Member] | Regulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	8,015,000		7,309,000		25,417,000		23,018,000
Energy Distribution [Member] | FPU Electric Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	23,121,000		29,051,000		60,569,000		58,972,000
Energy Distribution [Member] | FPU Electric Distribution [Member] | Regulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	23,121,000		29,051,000		60,569,000		58,972,000
Energy Distribution [Member] | Florida Public Utilities Company [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	22,012,000		19,935,000		72,032,000		64,877,000
Energy Distribution [Member] | Florida Public Utilities Company [Member] | Regulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	22,012,000		19,935,000		72,032,000		64,877,000
Energy Distribution [Member] | Maryland Natural Gas [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	2,432,000		2,824,000		16,122,000		15,941,000
Energy Distribution [Member] | Maryland Natural Gas [Member] | Regulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	2,432,000		2,824,000		16,122,000		15,941,000
Energy Distribution [Member] | Sandpiper [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	3,553,000		3,290,000		15,438,000		12,440,000
Energy Distribution [Member] | Sandpiper [Member] | Regulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	3,553,000		3,290,000		15,438,000		12,440,000
Energy Distribution [Member] | Elkton Gas [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	915,000				4,745,000
Energy Distribution [Member] | Elkton Gas [Member] | Regulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	915,000				4,745,000
Energy Transmission [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	30,636,000		28,271,000		100,878,000		90,346,000
Energy Transmission [Member] | Regulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	25,381,000		24,822,000		77,140,000		72,562,000
Energy Transmission [Member] | Unregulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	5,255,000		3,449,000		23,738,000		17,784,000
Energy Transmission [Member] | Aspire [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	5,255,000		3,449,000		23,738,000		17,784,000
Energy Transmission [Member] | Aspire [Member] | Unregulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	5,255,000		3,449,000		23,738,000		17,784,000
Energy Transmission [Member] | Eastern Shore Gas Company [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	18,558,000		18,389,000		57,147,000		55,944,000
Energy Transmission [Member] | Eastern Shore Gas Company [Member] | Regulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	18,558,000		18,389,000		57,147,000		55,944,000
Energy Transmission [Member] | Peninsula Pipeline [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	6,776,000		6,433,000		19,853,000		16,618,000
Energy Transmission [Member] | Peninsula Pipeline [Member] | Regulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	6,776,000		6,433,000		19,853,000		16,618,000
Energy Transmission [Member] | Aspire Energy Express | Regulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	47,000				140,000
Energy Generation [Member] | Eight Flags [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	4,583,000		3,882,000		13,086,000		11,898,000
Energy Generation [Member] | Eight Flags [Member] | Unregulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	4,583,000		3,882,000		13,086,000		11,898,000
Propane Delivery [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	20,680,000		13,710,000		99,041,000		69,593,000
Propane Delivery [Member] | Florida Propane | Unregulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	20,680,000		13,710,000		99,041,000		69,593,000
Energy Services [Member] | Marlin Gas Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,678,000				6,019,000
Energy Services [Member] | Marlin Gas Services [Member] | Unregulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,678,000		1,708,000		6,019,000		5,266,000
Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	(18,271,000)		(16,558,000)		(55,327,000)		(47,778,000)
Eliminations [Member] | Regulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	(12,882,000)		(12,335,000)		(40,148,000)		(34,766,000)
Eliminations [Member] | Unregulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	(87,000)		(35,000)		(242,000)		(75,000)
Eliminations [Member] | Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	(5,302,000)		(4,188,000)		(14,937,000)		(12,937,000)
Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	132,000		131,000		396,000		396,000
Other [Member] | Unregulated Energy [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	0				0		0
Other [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 132,000		$ 131,000		$ 396,000		$ 396,000
[1]	(1) Total operating revenues for the three months ended September 30, 2021, include other revenue (revenues from sources other than contracts with customers) of $0.1 million for both Regulated and Unregulated Energy segments, respectively, and $0.2 million and $0.05 million for our Regulated and Unregulated Energy segments, respectively, for the three months ended September 30, 2020. The sources of other revenues include revenue from alternative revenue programs related to revenue normalization for the Maryland division and Sandpiper Energy and late fees.
[2]	(1) Total operating revenues for the nine months ended September 30, 2021, include other revenue (revenues from sources other than contracts with customers) of $(0.1) million and $0.3 million for our Regulated and Unregulated Energy segments, respectively, and $1.0 million and $0.2 million for our Regulated and Unregulated Energy segments, respectively, for the nine months ended September 30, 2020. The sources of other revenues include revenue from alternative revenue programs related to revenue normalization for the Maryland division and Sandpiper Energy and late fees.

Revenue Recognition Contract Ba

Revenue Recognition Contract Balances with Customers (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Receivables from Customers	$ 40,683	$ 40,683	$ 55,600
Contract with Customer, Asset, Net, Current	18	18	18
Contract with Customer, Asset, Net, Noncurrent	5,011	5,011	4,816
Customer deposits and refunds	874	874	$ 644
Increase (Decrease) in Receivables		(14,917)
Increase (Decrease) in Other Current Assets		0
Increase (Decrease) in Other Noncurrent Assets		195
Increase (Decrease) in Other Current Liabilities		230
Contract with Customer, Liability, Revenue Recognized	$ 200	$ 800

Revenue Recognition Remaining P

Revenue Recognition Remaining Performance Obligations (Details) $ in Thousands	Sep. 30, 2021USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Revenue from Contract with Customer [Abstract]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period
FPU Electric Distribution [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 163
FPU Electric Distribution [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	652
FPU Electric Distribution [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	652
FPU Electric Distribution [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	652
FPU Electric Distribution [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	275
FPU Electric Distribution [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	275
FPU Electric Distribution [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	550
Natural gas distribution operations [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	1,752
Natural gas distribution operations [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	6,620
Natural gas distribution operations [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	6,044
Natural gas distribution operations [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	5,811
Natural gas distribution operations [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	5,271
Natural gas distribution operations [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	5,064
Natural gas distribution operations [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	33,448
Eastern Shore and Peninsula Pipeline [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	9,471
Eastern Shore and Peninsula Pipeline [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	32,796
Eastern Shore and Peninsula Pipeline [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	25,205
Eastern Shore and Peninsula Pipeline [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	22,975
Eastern Shore and Peninsula Pipeline [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	22,102
Eastern Shore and Peninsula Pipeline [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	21,023
Eastern Shore and Peninsula Pipeline [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	179,728
Total for Segments [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	11,386
Total for Segments [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	40,068
Total for Segments [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	31,901
Total for Segments [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	29,438
Total for Segments [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	27,648
Total for Segments [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	26,362
Total for Segments [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 213,726

Rates and Other Regulatory Ac_3

Rates and Other Regulatory Activities - Additional Information (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2021USD ($)Dekathermcustomermi	Dec. 31, 2020USD ($)
Rates and Other Regulatory Activities [Line Items]
Regulatory Asset - Storm Cost Recovery	$ 45,800
Surcharge - Storm Cost Recovery	7,700
Incremental Revenue - Storm Cost Recovery	3,300
COVID-19 Regulatory Asset	2,300	$ 1,900
Florida Public Utilities Company [Member]
Rates and Other Regulatory Activities [Line Items]
COVID-19 Settlement Amount	2,100
Delmarva [Member]
Rates and Other Regulatory Activities [Line Items]
COVID-19 Settlement Amount	300
Delaware natural gas division [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	12,626	12,728
Maryland Division [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	3,873	3,970
Sandpiper [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	3,670	3,713
Central Florida Gas Division [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	8,070	8,184
Florida Public Utilities Company [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	19,132	19,257
Fort Meade and Indiantown Divisions [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	274	309
FPU electric division [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	5,299	6,694
Eastern Shore Gas Company [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	34,190	34,190
Elkton Gas [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	$ 1,124	$ 1,124
Del-Mar Pathway Project [Member] | Eastern Shore Gas Company [Member]
Rates and Other Regulatory Activities [Line Items]
Number of Mainline Pipeline Miles | mi	13
Additional Firm Natural Gas Transportation Deliverability | Dekatherm	14,300
number of customers | customer	4
Number of Pipeline Miles | mi	6
Beachside Expansion | Peninsula Pipeline Company [Member]
Rates and Other Regulatory Activities [Line Items]
Number of Mainline Pipeline Miles | mi	11.3
Additional Firm Natural Gas Transportation Deliverability | Dekatherm	10,176
Winter Haven Expansion | Peninsula Pipeline Company [Member]
Rates and Other Regulatory Activities [Line Items]
Additional Firm Natural Gas Transportation Deliverability | Dekatherm	6,800
Regulated Energy [Member] | Escambia Meter
Rates and Other Regulatory Activities [Line Items]
Additional Firm Natural Gas Transportation Deliverability | Dekatherm	530,000

Environmental Commitments and_3

Environmental Commitments and Contingencies - Additional Information (Detail)	3 Months Ended	9 Months Ended
	Mar. 31, 2021USD ($)	Sep. 30, 2021USD ($)site	Dec. 31, 2020USD ($)
Environmental Commitments And Contingencies [Line Items]
Company's exposure in number of former Manufactured Gas Plant Sites | site		7
Environmental liabilities		$ 3,709,000	$ 4,299,000
West Palm Beach Florida [Member] | Minimum [Member]
Environmental Commitments And Contingencies [Line Items]
Estimated costs of remediation range, minimum		3,300,000
West Palm Beach Florida [Member] | Maximum [Member]
Environmental Commitments And Contingencies [Line Items]
Estimated costs of remediation range, minimum		14,200,000
Winter Haven Florida [Member] | Maximum [Member]
Environmental Commitments And Contingencies [Line Items]
Environmental remediation expense		400,000
Seaford [Member] | Minimum [Member]
Environmental Commitments And Contingencies [Line Items]
Estimated costs of remediation range, minimum		300,000
Seaford [Member] | Maximum [Member]
Environmental Commitments And Contingencies [Line Items]
Estimated costs of remediation range, minimum		900,000
FPU [Member]
Environmental Commitments And Contingencies [Line Items]
Environmental liabilities		5,400,000	5,900,000
Approval of recovery of environmental costs		14,000,000
Environmental costs recovered	$ 12,400,000	12,700,000
FPU [Member] | Manufactured Gas Plant [Member]
Environmental Commitments And Contingencies [Line Items]
Regulatory Assets for future recovery of environmental costs		$ 1,300,000	$ 1,600,000

Other Commitments and Conting_2

Other Commitments and Contingencies - Additional Information (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2021USD ($)
Other Commitments [Line Items]
Debt Service Coverage Ratio	1.25
Debt Service Coverage Ratio Measurement Period	12
Maximum Days To Make Default Good	5 days
Ratio based on average number of prior quarters	6
Ratios based on average of the prior quarters	1 year 6 months
Funds from operations interest coverage ratio minimum times	2
Total debt to capital maximum	0.65
Number Of Years For Power Purchase Agreement	20 years
Contract Duration	20 years
Aggregate guaranteed amount	$ 20
Guarantor Obligations, Current Carrying Value	8
Draws on letters of credit	$ 4.6
Florida Natural Gas Distribution and Eight Flags [Member]
Other Commitments [Line Items]
Number of Years for Asset Management Agreement	10 years
Delmarva [Member]
Other Commitments [Line Items]
Number of Years for Asset Management Agreement	3 years

Segment Information - Schedule

Segment Information - Schedule of Segment Reporting Information by Segment (Detail) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Dec. 31, 2020USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments				2
Operating Revenues, Unaffiliated Customers
Total operating revenues, unaffiliated customers		$ 107,335	$ 101,419	$ 409,604	$ 351,160
Operating Income
Total operating income		20,113	17,406	94,288	77,518
Other expense, net		339	(40)	2,180	2,997
Interest		4,975	4,584	15,134	15,452
Income Before Income Taxes		15,477	12,782	81,334	65,063
Income Taxes on Continuing Operations		2,993	3,502	20,563	16,082
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent		12,484	9,280	60,771	48,981
Net Income		12,475	9,261	60,754	49,146
Identifiable Assets
Total identifiable assets		2,021,828		2,021,828		$ 1,932,487
Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, Net of Tax		(9)	(19)	(17)	165
Regulated Energy [Member]
Operating Income
Total operating income		23,538	20,482	79,210	66,376
Identifiable Assets
Total identifiable assets		1,592,950		1,592,950		1,547,619
Unregulated Energy [Member]
Operating Income
Total operating income		(2,883)	(3,092)	15,777	11,050
Identifiable Assets
Total identifiable assets		381,642		381,642		347,665
Other [Member]
Identifiable Assets
Total identifiable assets		47,236		47,236		$ 37,203
Other and eliminations [Member]
Operating Income
Total operating income		(542)	16	(699)	92
Operating Revenues, Unaffiliated Customers [Member]
Operating Revenues, Unaffiliated Customers
Total operating revenues, unaffiliated customers		107,335	101,419	409,604	351,160
Operating Revenues, Unaffiliated Customers [Member] | Regulated Energy [Member]
Operating Revenues, Unaffiliated Customers
Total operating revenues, unaffiliated customers		79,892	82,297	280,987	257,810
Operating Revenues, Unaffiliated Customers [Member] | Unregulated Energy [Member]
Operating Revenues, Unaffiliated Customers
Total operating revenues, unaffiliated customers		27,443	19,122	128,617	93,350
Intersegment Revenues [Member]
Operating Revenues, Unaffiliated Customers
Total operating revenues, unaffiliated customers	[1]	5,302	4,188	14,937	12,937
Intersegment Revenues [Member] | Regulated Energy [Member]
Operating Revenues, Unaffiliated Customers
Total operating revenues, unaffiliated customers	[1]	504	465	1,516	1,425
Intersegment Revenues [Member] | Unregulated Energy [Member]
Operating Revenues, Unaffiliated Customers
Total operating revenues, unaffiliated customers	[1]	4,666	3,592	13,024	11,116
Intersegment Revenues [Member] | Other [Member]
Operating Revenues, Unaffiliated Customers
Total operating revenues, unaffiliated customers	[1]	132	131	397	396
Retained Earnings [Member]
Operating Income
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent		12,484	9,280	60,771	48,981
Net Income		$ 12,475	$ 9,261	$ 60,754	$ 49,146
[1]	All significant intersegment revenues are billed at market rates and have been eliminated from consolidated operating revenues.

Stockholder's Equity - Accumu_3

Stockholder's Equity - Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ / shares in Units, shares in Millions	1 Months Ended	3 Months Ended			6 Months Ended	9 Months Ended
	Oct. 31, 2021	Sep. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ 2,439,000		$ (2,865,000)		$ (2,865,000)	$ (2,865,000)	$ (6,267,000)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax						8,176,000	3,617,000
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax						(2,872,000)	(979,000)
Net current-period other comprehensive income (loss)		$ 1,881,000		$ 833,000		5,304,000	2,638,000
Ending balance		2,439,000		(3,629,000)		$ 2,439,000	(3,629,000)
Stock Issued During Period, Shares, Dividend Reinvestment Plan	0.1		0.3			0.1
Stock Issued During Period, Value, Dividend Reinvestment Plan	$ 127.40		$ 86.12			$ 116.63
Proceeds from Issuance of Common Stock, Dividend Reinvestment Plan	$ 1,800,000		$ 22,000,000			$ 6,600,000
Common Stock Shares Issued At The Market								0.7
Shares Issued Price Per Share - At The Market								$ 82.93
Proceeds From Issuance Of Common Stock - At The Market					61,000,000
Stock Issued During Period, Shares, Dividend Reinvestment Plan	0.1		0.3			0.1
Stock Issued During Period, Value, Dividend Reinvestment Plan	$ 127.40		$ 86.12			$ 116.63
Proceeds from Issuance of Common Stock, Dividend Reinvestment Plan	1,800,000		22,000,000			6,600,000
Fees on Equity Issuance - At The Market					1,500,000
Maximum [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Proceeds from Stock Plans			75,000,000
Proceeds from Stock Plans			75,000,000
UnrealizedGainsLossesFromDefinedBenefitPensionAndPostretirementPlanItems [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(4,954,000)		(5,146,000)		(5,146,000)	(5,146,000)	(4,933,000)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax						0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax						192,000	198,000
Net current-period other comprehensive income (loss)						192,000	198,000
Ending balance		(4,954,000)		(4,735,000)		(4,954,000)	(4,735,000)
Accumulated (Gain) Loss from Commodity Contracts Cash Flows Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	7,403,000		2,309,000		2,309,000	2,309,000	(1,334,000)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax						8,121,000	3,594,000
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax						(3,027,000)	(1,144,000)
Net current-period other comprehensive income (loss)						5,094,000	2,450,000
Ending balance		7,403,000		1,116,000		7,403,000	1,116,000
Accumulated (Gain) Loss from Interest Rate Swap Cash Flows Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (10,000)		$ (28,000)		$ (28,000)	(28,000)	0
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax						55,000	23,000
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax						(37,000)	(33,000)
Net current-period other comprehensive income (loss)						18,000	(10,000)
Ending balance		$ (10,000)		$ (10,000)		$ (10,000)	$ (10,000)

Stockholder's Equity - Accumu_4

Stockholder's Equity - Accumulated Other Comprehensive Income (Loss) - Reclassifications of Accumulated Other Comprehensive Loss (Detail) - USD ($) shares in Millions		1 Months Ended	3 Months Ended			9 Months Ended
		Oct. 31, 2021	Sep. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Amortization of pension and postretirement items:
Tax benefit			$ (2,993,000)		$ (3,502,000)	$ (20,563,000)	$ (16,082,000)
Derivative, Gain (Loss) on Derivative, Net			3,215,000		1,209,000	$ 11,272,000	4,997,000
Stock Issued During Period, Shares, Dividend Reinvestment Plan		0.1		0.3		0.1
Stock Issued During Period, Value, Dividend Reinvestment Plan		$ 127.40		$ 86.12		$ 116.63
Proceeds from Issuance of Common Stock, Dividend Reinvestment Plan		$ 1,800,000		$ 22,000,000		6,600,000
Reclassification out of Accumulated Other Comprehensive Income [Member]
Amortization of pension and postretirement items:
Net of tax			447,000		43,000	2,872,000	979,000
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment [Member]
Amortization of pension and postretirement items:
Prior service cost	[1]		19,000		19,000	57,000	57,000
Net loss	[1]		(106,000)		(108,000)	(317,000)	(323,000)
Total before tax			(87,000)		(89,000)	(260,000)	(266,000)
Tax benefit			23,000		23,000	68,000	68,000
Net of tax			(64,000)		(66,000)	(192,000)	(198,000)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated (Gain) Loss from Commodity Contracts Cash Flows Hedges [Member]
Amortization of pension and postretirement items:
Tax benefit			(188,000)		(32,000)	(1,156,000)	(437,000)
Net of tax			493,000		84,000	3,027,000	1,144,000
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated (Gain) Loss from Interest Rate Swap Cash Flows Hedges [Member]
Amortization of pension and postretirement items:
Other Comprehensive Income Loss Adjustments AOCI Swap Agreements					34,000		45,000
Tax benefit			(6,000)		(9,000)	(13,000)	(12,000)
Net of tax			18,000		25,000	37,000	33,000
Propane Swap Agreement [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated (Gain) Loss from Commodity Contracts Cash Flows Hedges [Member]
Amortization of pension and postretirement items:
Other Comprehensive Income Loss Adjustments AOCI Swap Agreements	[2]		681,000		116,000	4,183,000	1,581,000
Interest Rate Swap [Member] | Derivatives designated as hedging instrument [Member] | Interest Expense [Member]
Amortization of pension and postretirement items:
Derivative, Gain (Loss) on Derivative, Net			$ 24,000		$ 34,000	$ 50,000	$ 45,000
[1]	These amounts are included in the computation of net periodic costs (benefits). See Note 10 , Employee Benefit Plans , for additional details.
[2]	These amounts are included in the effects of gains and losses from derivative instruments. See Note 13, Derivative Instruments , for additional details.

Employee Benefit Plans (Detail)

Employee Benefit Plans (Detail) - USD ($) $ in Thousands		3 Months Ended				9 Months Ended
		Sep. 30, 2021		Sep. 30, 2020		Sep. 30, 2021	Sep. 30, 2020
Defined Benefit Plan Disclosure [Line Items]
Amortization of prior service cost		$ (19)		$ (19)		$ (57)	$ (57)
Defined Benefit Plan Actuarial Gain Loss, Net Settlement				198			594
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		230		217		690	651
Defined Benefit Plan Amounts Recognized Gain (Loss)		211		198		633	594
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax	[1]	87		89		260	267
Defined Benefit Plan Amounts Recognized From Regulatory Asset		124		109		373	327
Chesapeake Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Contributions by Employer		200				300
Interest cost		34		46		102	138
Expected return on plan assets		(40)		(42)		(120)	(126)
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		60		65		180	195
Net periodic cost (benefit)		54	[1]	69	[1]	162	207
Total periodic cost		54		69		162	207
Defined Benefit Plan Amounts Recognized Gain (Loss)		60		65		180	195
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax	[1]	60		65		180	195
Florida Public Utilities Company Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Contributions by Employer		500				1,300
Interest cost		429		518		1,287	1,554
Expected return on plan assets		(830)		(745)		(2,490)	(2,235)
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		155		135		465	405
Net periodic cost (benefit)		(246)	[1]	(92)	[1]	(738)	(276)
Amortization of pre-merger regulatory asset		0		0		0	0
Total periodic cost		(246)		(92)		(738)	(276)
Defined Benefit Plan Amounts Recognized Gain (Loss)		155		135		465	405
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax	[1]	29		26		87	78
Defined Benefit Plan Amounts Recognized From Regulatory Asset		126		109		378	327
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year		2,100				2,100
Chesapeake Pension SERP [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Contributions by Employer		100
Interest cost		12		16		36	48
Defined Benefit Plan Actuarial Gain Loss, Net Settlement				5			15
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		7		5		21	15
Net periodic cost (benefit)		19	[1]	21	[1]	57	63
Total periodic cost		19		21		57	63
Defined Benefit Plan Amounts Recognized Gain (Loss)		7		5		21	15
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax	[1]	7		5		21	15
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year		200				200
Chesapeake Postretirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Contributions by Employer						200
Interest cost		6		8		18	24
Amortization of prior service cost		(19)		(19)		(57)	(57)
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		10		12		30	36
Net periodic cost (benefit)		(3)	[1]	1	[1]	(9)	3
Total periodic cost		(3)		1		(9)	3
Defined Benefit Plan Amounts Recognized Gain (Loss)		(9)		(7)		(27)	(21)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax	[1]	(9)		(7)		(27)	(21)
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year		200				200
Florida Public Utilities Company Medical Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Contributions by Employer						100
Interest cost		6		10		18	30
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		(2)				(6)
Net periodic cost (benefit)		4	[1]	10	[1]	12	30
Amortization of pre-merger regulatory asset		0		2		0	6
Total periodic cost		4		$ 12		12	$ 36
Defined Benefit Plan Amounts Recognized Gain (Loss)		(2)				(6)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax	[1]					(1)
Defined Benefit Plan Amounts Recognized From Regulatory Asset		(2)				(5)
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year		$ 100				$ 100
[1]	See Note 9 , Stockholders' Equity

Employee Benefit Plans - Additi

Employee Benefit Plans - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Defined Benefit Plan Disclosure [Line Items]
Amortization of prior service cost		$ (19)	$ (19)	$ (57)	$ (57)
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		230	217	690	651
Defined Benefit Plan Amounts Recognized Gain (Loss)		211	198	633	594
Recognized from accumulated other comprehensive loss	[1]	87	89	260	267
Recognized from regulatory asset		124	109	373	327
Defined Benefit Plan Actuarial Gain Loss, Net Settlement			198		594
Florida Public Utilities Company Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution to pension plan		500		1,300
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year		2,100		2,100
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		155	135	465	405
Defined Benefit Plan Amounts Recognized Gain (Loss)		155	135	465	405
Recognized from accumulated other comprehensive loss	[1]	29	26	87	78
Recognized from regulatory asset		126	109	378	327
Chesapeake Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution to pension plan		200		300
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		60	65	180	195
Defined Benefit Plan Amounts Recognized Gain (Loss)		60	65	180	195
Recognized from accumulated other comprehensive loss	[1]	60	65	180	195
Chesapeake Pension SERP [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution to pension plan		100
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year		200		200
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		7	5	21	15
Defined Benefit Plan Amounts Recognized Gain (Loss)		7	5	21	15
Recognized from accumulated other comprehensive loss	[1]	7	5	21	15
Defined Benefit Plan Actuarial Gain Loss, Net Settlement			5		15
Chesapeake Postretirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution to pension plan				200
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year		200		200
Amortization of prior service cost		(19)	(19)	(57)	(57)
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		10	12	30	36
Defined Benefit Plan Amounts Recognized Gain (Loss)		(9)	(7)	(27)	(21)
Recognized from accumulated other comprehensive loss	[1]	(9)	$ (7)	(27)	$ (21)
Florida Public Utilities Company Medical Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution to pension plan				100
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year		100		100
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		(2)		(6)
Defined Benefit Plan Amounts Recognized Gain (Loss)		(2)		(6)
Recognized from accumulated other comprehensive loss	[1]			(1)
Recognized from regulatory asset		$ (2)		$ (5)
[1]	See Note 9 , Stockholders' Equity

Employee Benefit Plans - Amount

Employee Benefit Plans - Amounts Included in Regulatory Asset and Accumulated Other Comprehensive Income/Loss Recognized as Net Periodic Benefit Cost (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Prior service cost (credit)		$ (19)	$ (19)	$ (57)	$ (57)
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		230	217	690	651
Recognized from accumulated other comprehensive loss	[1]	87	89	260	267
Recognized from regulatory asset		124	109	373	327
Defined Benefit Plan Actuarial Gain Loss, Net Settlement			198		594
Total recognized in net periodic benefit cost		211	198	633	594
Chesapeake Pension Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		60	65	180	195
Recognized from accumulated other comprehensive loss	[1]	60	65	180	195
Total recognized in net periodic benefit cost		60	65	180	195
Florida Public Utilities Company Pension Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		155	135	465	405
Recognized from accumulated other comprehensive loss	[1]	29	26	87	78
Recognized from regulatory asset		126	109	378	327
Total recognized in net periodic benefit cost		155	135	465	405
Chesapeake Pension SERP [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		7	5	21	15
Recognized from accumulated other comprehensive loss	[1]	7	5	21	15
Defined Benefit Plan Actuarial Gain Loss, Net Settlement			5		15
Total recognized in net periodic benefit cost		7	5	21	15
Chesapeake Postretirement Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Prior service cost (credit)		(19)	(19)	(57)	(57)
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		10	12	30	36
Recognized from accumulated other comprehensive loss	[1]	(9)	(7)	(27)	(21)
Total recognized in net periodic benefit cost		(9)	$ (7)	(27)	$ (21)
Florida Public Utilities Company Medical Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		(2)		(6)
Recognized from accumulated other comprehensive loss	[1]			(1)
Recognized from regulatory asset		(2)		(5)
Total recognized in net periodic benefit cost		$ (2)		$ (6)
[1]	See Note 9 , Stockholders' Equity

Investments - Schedule of Inves

Investments - Schedule of Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Investments schedule [Line Items]
Investments, at fair value	$ 11,490	$ 10,776
Rabbi Trust Associated With Deferred Compensation Plan [Member]
Investments schedule [Line Items]
Investments, at fair value	11,467	10,755
Equity Securities [Member]
Investments schedule [Line Items]
Investments, at fair value	$ 23	$ 21

Investments - Additional Inform

Investments - Additional Information (Detail) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Investments, Debt and Equity Securities [Abstract]
Unrealized gain (loss), net of other expenses	$ 600,000	$ 1,000,000	$ 400,000

Share-Based Compensation - Shar

Share-Based Compensation - Share-Based Compensation Amounts Included in Net Income (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 31, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation expense		$ 1,306	$ 1,332	$ 4,620	$ 3,654
Less: tax benefit		(339)	(348)	(1,200)	(955)
Share-Based Compensation amounts included in net income		967	984	$ 3,420	2,699
Awards to non-employee directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	342			683
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 129.09			$ 117.11
Total compensation expense		$ 201	188	$ 581	545
Award to key employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number		196,057		196,057		186,878
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				68,562
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period				53,147
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Expired In Period				(852)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value		$ 94.15		$ 94.15		$ 87.06
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value				102.73
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value				76.31
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Expirations Weighted Average Grant Date Fair Value				$ 74.85
Total compensation expense		$ 1,105	$ 1,144	$ 4,039	$ 3,109

Share-Based Compensation - Summ

Share-Based Compensation - Summary of Stock Activity under the SICP (Detail) - $ / shares	1 Months Ended	3 Months Ended	9 Months Ended
	Oct. 31, 2021	Sep. 30, 2021	Sep. 30, 2021
Award to key employees [Member]
Number of Shares
Outstanding - December 31, 2020 (shares)	196,057		186,878
Granted awards (shares)			68,562
Vested (shares)			(53,147)
Expired (shares)			852
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period		(5,384)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value		$ 93.39
Outstanding - June 30, 2021 (shares)		196,057	196,057
Weighted Average Fair Value
Outstanding - December 31, 2020 (in dollars per share)	$ 94.15		$ 87.06
Granted (in dollars per share)			102.73
Vested (in dollars per share)			76.31
Expired (in dollars per share)			74.85
Outstanding - June 30, 2021 (in dollars per share)		$ 94.15	$ 94.15
Awards to non-employee directors [Member]
Number of Shares
Granted awards (shares)	342		683
Weighted Average Fair Value
Granted (in dollars per share)	$ 129.09		$ 117.11

Share-Based Compensation - Addi

Share-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
	Oct. 31, 2021	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation			14,020	10,319
Payment, Tax Withholding, Share-based Payment Arrangement			$ 1,478	$ 977
Unrecognized compensation cost		$ 5,600	$ 5,600
Awards to non-employee directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 129.09		$ 117.11
Granted awards (shares)	342		683
Unrecognized compensation expense related to the awards to non-employee directors		500	$ 500
Shares awarded to non-employee directors [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 129.09		$ 117.11
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	342		683
Total [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted awards (shares)			6,830
Shares awarded to non-employee directors [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			6,830
Award to key employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Expired In Period			(852)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 102.73
Granted awards (shares)			68,562
Vesting period			3 years
Payment, Tax Withholding, Share-based Payment Arrangement			$ 1,500
Intrinsic value of the SICP awards		$ 23,500	$ 23,500
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period		(5,384)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value		$ 93.39
Shares awarded to non-employee directors [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 102.73
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			68,562
Accelerated Vested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation			14,020

Derivative Instruments Volume o

Derivative Instruments Volume of Derivative Activity (Details) - Sharp Energy Inc [Member] gal in Millions, $ in Millions	9 Months Ended
	Sep. 30, 2021USD ($)gal
Derivative [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months | $	$ 6.2
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimate of Time to Transfer	12 months
Swap Purchases
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume	23.4
Swap Sales
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume	5

Derivative Instruments - Additi

Derivative Instruments - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
	Feb. 28, 2021	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2020
Derivative [Line Items]
Energy Marketing Contracts Assets, Current		$ 12,185	$ 12,185	$ 3,269
Energy Marketing Contract Liabilities, Current		(1,969)	(1,969)	(127)
Notional Amount of Nonderivative Instruments	$ 40,000	70,000	30,000
Notional Amount Nonderivative Instruments, Total			60,000
Interest Rate Swap [Member]
Derivative [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months			100
Designated as Hedging Instrument [Member] | Mark To Market Energy Assets [Member] | Propane Swap Agreement [Member]
Derivative [Line Items]
Energy Marketing Contracts Assets, Current		12,185	12,185	3,255
Designated as Hedging Instrument [Member] | Mark-to-market energy liabilities [Member] | Interest Rate Swap [Member]
Derivative [Line Items]
Energy Marketing Contract Liabilities, Current		(15)	(15)	(40)
Designated as Hedging Instrument [Member] | Mark-to-market energy liabilities [Member] | Propane Swap Agreement [Member]
Derivative [Line Items]
Energy Marketing Contract Liabilities, Current		(1,954)	(1,954)	(64)
Sharp Energy Inc [Member]
Derivative [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months			$ 6,200
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimate of Time to Transfer			12 months
Other Payables to Broker-Dealers and Clearing Organizations		$ 6,094	$ 6,094	$ 1,505
Interest Rate Swap Rate, High Range [Member]
Derivative [Line Items]
Fixed Swap Rate		0.17%	0.17%	0.205%
Interest Rate Swap Rate, Low Range [Member]
Derivative [Line Items]
Fixed Swap Rate				0.20%

Derivative Instruments - Fair V

Derivative Instruments - Fair Values of Derivative Contracts Recorded in Condensed Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Energy Marketing Contracts Assets, Current	$ 12,185	$ 3,269
Energy Marketing Contract Liabilities, Current	1,969	127
Mark To Market Energy Assets [Member] | Propane Swap Agreement [Member] | Derivatives designated as hedging instrument [Member]
Derivatives, Fair Value [Line Items]
Energy Marketing Contracts Assets, Current	12,185	3,255
Mark To Market Energy Assets [Member] | Put Option [Member] | Derivatives designated as hedging instrument [Member]
Derivatives, Fair Value [Line Items]
Energy Marketing Contracts Assets, Current		14
Energy Marketing Contract Liabilities, Current		23
Mark-to-market energy liabilities [Member] | Propane Swap Agreement [Member] | Derivatives designated as hedging instrument [Member]
Derivatives, Fair Value [Line Items]
Energy Marketing Contract Liabilities, Current	1,954	64
Mark-to-market energy liabilities [Member] | Interest Rate Swap [Member] | Derivatives designated as hedging instrument [Member]
Derivatives, Fair Value [Line Items]
Energy Marketing Contract Liabilities, Current	$ 15	$ 40

Derivative Instruments - Effect

Derivative Instruments - Effects of Gains and Losses from Derivative Instruments on Condensed Consolidated Financial Statements (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 3,215	$ 1,209	$ 11,272	$ 4,997
Cost of Sales [Member] | Derivatives designated as hedging instrument [Member] | Propane Swap Agreement [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	681	116	4,183	1,581
Cost of Sales [Member] | Derivatives designated as hedging instrument [Member] | Put Or Call Option
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	0		(24)
Other Comprehensive Income (Loss) [Member] | Derivatives designated as hedging instrument [Member] | Propane Swap Agreement [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax	2,491	1,022	7,039	3,385
Other Comprehensive Income (Loss) [Member] | Derivatives designated as hedging instrument [Member] | Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax	19	37	24	(14)
Interest Expense [Member] | Derivatives designated as hedging instrument [Member] | Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 24	$ 34	$ 50	$ 45

Fair Value of Financial Instr_3

Fair Value of Financial Instruments - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets:
Investments	$ 11,490	$ 10,776
Energy Marketing Contracts Assets, Current	12,185	3,269
Liabilities:
Energy Marketing Contract Liabilities, Current	1,969	127
Equity Securities [Member]
Assets:
Investments	23	21
Quoted Prices in Active Markets (Level 1) [Member]
Assets:
Assets, Fair Value Disclosure	9,474	8,620
Quoted Prices in Active Markets (Level 1) [Member] | Equity Securities [Member]
Assets:
Investments	23	21
Quoted Prices in Active Markets (Level 1) [Member] | Investments - Mutual funds and other [Member]
Assets:
Investments	9,451	8,599
Quoted Prices in Active Markets (Level 1) [Member] | Total Investments [Member]
Assets:
Investments	9,474	8,620
Significant Other Observable Inputs (Level 2) [Member]
Assets:
Assets, Fair Value Disclosure	12,185	3,269
Significant Unobservable Inputs (Level 3) [Member]
Assets:
Assets, Fair Value Disclosure	2,016	2,156
Significant Unobservable Inputs (Level 3) [Member] | Investments in guaranteed income fund [Member]
Assets:
Investments	2,016	2,156
Significant Unobservable Inputs (Level 3) [Member] | Total Investments [Member]
Assets:
Investments	2,016	2,156
Recurring [Member]
Assets:
Assets, Fair Value Disclosure	23,675	14,045
Liabilities:
Energy Marketing Contract Liabilities, Current		127
Recurring [Member] | Equity Securities [Member]
Assets:
Investments	23	21
Recurring [Member] | Investments in guaranteed income fund [Member]
Assets:
Investments	2,016	2,156
Recurring [Member] | Investments - Mutual funds and other [Member]
Assets:
Investments		8,599
Recurring [Member] | Total Investments [Member]
Assets:
Investments	$ 11,490	10,776
Recurring [Member] | Mark To Market Energy Assets incl. natural gas and swap agreements[Member]
Assets:
Derivative assets		$ 3,269

Fair Value of Financial Instr_4

Fair Value of Financial Instruments - Summary of Changes in Fair Value of Investments (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, at fair value	$ 11,490		$ 10,776
Derivative assets, at fair value	12,185		3,269
Energy Marketing Contract Liabilities, Current	1,969		127
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	(241)	$ (514)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	2,156	803
Purchases and adjustments	77	243
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0	1,579
Investment Income	24	18
Ending Balance	2,016	$ 2,129
Quoted Prices in Active Markets (Level 1) [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Assets, Fair Value Disclosure	9,474		8,620
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Assets, Fair Value Disclosure	12,185		3,269
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Assets, Fair Value Disclosure	2,016		2,156
Recurring [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Assets, Fair Value Disclosure	23,675		14,045
Energy Marketing Contract Liabilities, Current			127
Equity Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, at fair value	23		21
Equity Securities [Member] | Quoted Prices in Active Markets (Level 1) [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, at fair value	23		21
Equity Securities [Member] | Recurring [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, at fair value	23		21
Investments in guaranteed income fund [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, at fair value	2,016		2,156
Investments in guaranteed income fund [Member] | Recurring [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, at fair value	2,016		2,156
Investments - Mutual funds and other [Member] | Quoted Prices in Active Markets (Level 1) [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, at fair value	9,451		8,599
Investments - Mutual funds and other [Member] | Recurring [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, at fair value			8,599
Total Investments [Member] | Quoted Prices in Active Markets (Level 1) [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, at fair value	9,474		8,620
Total Investments [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, at fair value	2,016		2,156
Total Investments [Member] | Recurring [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, at fair value	$ 11,490		10,776
Mark To Market Energy Assets Including Put Option [Member] | Recurring [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset			$ 3,269

Fair Value of Financial Instr_5

Fair Value of Financial Instruments - Additional Information (Detail) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Long-term debt including current maturities	$ 522.5	$ 523
Fair value of long-term debt	$ 561.9	$ 548.5

Long-Term Debt - Outstanding Lo

Long-Term Debt - Outstanding Long-Term Debt (Detail) - USD ($) $ in Thousands		Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total long-term debt		$ (522,500)	$ (523,000)
Debt Instrument, Unused Borrowing Capacity, Amount		310,000
Total Long-term debt		521,665	522,099
Less: current maturities		(16,206)	(13,600)
Less: debt issuance costs		825	901
Total long-term debt, net of current maturities		505,459	508,499
Aggregated Unfunded Commitments [Member]
Debt Instrument [Line Items]
Total long-term debt		0
New York Life [Member]
Debt Instrument [Line Items]
Total long-term debt	[1]	$ (140,000)
9.08% bond, due June 1, 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		9.08%
5.50% note, due October 12, 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		5.50%
5.93% note, due October 31, 2023 [Member]
Debt Instrument [Line Items]
Total long-term debt		$ (7,500)	(9,000)
Debt Instrument, Interest Rate, Stated Percentage		5.93%
5.68% note, due June 30, 2026 [Member]
Debt Instrument [Line Items]
Total long-term debt		$ (14,500)	(17,400)
Debt Instrument, Interest Rate, Stated Percentage		5.68%
6.43% note, due May 2, 2028 [Member]
Debt Instrument [Line Items]
Total long-term debt		$ (4,900)	(5,600)
Debt Instrument, Interest Rate, Stated Percentage		6.43%
3.73% note, due December 16, 2028 [Member]
Debt Instrument [Line Items]
Total long-term debt		$ (16,000)	(16,000)
Debt Instrument, Interest Rate, Stated Percentage		3.73%
3.88% note, due May 15, 2029 [Member]
Debt Instrument [Line Items]
Total long-term debt		$ (40,000)	(45,000)
Debt Instrument, Interest Rate, Stated Percentage		3.88%
3.25% note, due April 30, 2032 [Member]
Debt Instrument [Line Items]
Total long-term debt		$ (70,000)	(70,000)
3.48% note, due May 31, 2038 [Member]
Debt Instrument [Line Items]
Total long-term debt		(50,000)	(50,000)
Uncollateralized Senior Note Due November Two Thousand Thirty Eight [Member]
Debt Instrument [Line Items]
Total long-term debt		$ (50,000)	(50,000)
Debt Instrument, Interest Rate, Stated Percentage		3.58%
Uncollateralized Senior Note Due July Two Thousand Thirty Five
Debt Instrument [Line Items]
Total long-term debt		$ (50,000)	(50,000)
Debt Instrument, Interest Rate, Stated Percentage		3.00%
Uncollateralized Senior Note Due August Two Thousand Thirty Five
Debt Instrument [Line Items]
Total long-term debt		$ (40,000)	(40,000)
Debt Instrument, Interest Rate, Stated Percentage		2.96%
Uncollateralized Senior Note Due November Two Thousand Thirty Nine
Debt Instrument [Line Items]
Total long-term debt		$ (100,000)	$ (100,000)
Equipment Security Note
Debt Instrument [Line Items]
Total long-term debt		$ (9,590)
Debt Instrument, Interest Rate, Stated Percentage		2.46%
Equipment Security Note | Marlin Gas Services [Member]
Debt Instrument [Line Items]
Total long-term debt		$ (9,600)
Note Purchase Agreement
Debt Instrument [Line Items]
Total long-term debt		$ (50,000)
Debt Instrument, Interest Rate, Stated Percentage		2.49%
Aggregate Shelf Agreements [Member]
Debt Instrument [Line Items]
Total long-term debt		$ (360,000)
Aggregate Shelf Agreements [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		670,000
Prudential [Member]
Debt Instrument [Line Items]
Total long-term debt	[1]	(220,000)
Debt Instrument, Unused Borrowing Capacity, Amount	[1]	150,000
Prudential [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	[1]	370,000
MetLife [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	[1]	150,000
Debt Instrument, Unused Borrowing Capacity, Amount	[1]	$ 150,000
[1]	(1) The Prudential, MetLife and NYL Shelf Agreements expire in April 2023, May 2023 and November 2021, respectively.

Long-Term Debt - Outstanding _2

Long-Term Debt - Outstanding Long-Term Debt- Supplemental Information (Detail)	9 Months Ended
	Sep. 30, 2021
9.08% bond, due June 1, 2022 [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Jun. 1, 2022
Debt Instrument, Interest Rate, Stated Percentage	9.08%
5.50% note, due October 12, 2020 [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Oct. 12, 2020
Debt Instrument, Interest Rate, Stated Percentage	5.50%
5.93% note, due October 31, 2023 [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Oct. 31, 2023
Debt Instrument, Interest Rate, Stated Percentage	5.93%
5.68% note, due June 30, 2026 [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Jun. 30, 2026
Debt Instrument, Interest Rate, Stated Percentage	5.68%
6.43% note, due May 2, 2028 [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	May 2, 2028
Debt Instrument, Interest Rate, Stated Percentage	6.43%
3.73% note, due December 16, 2028 [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Dec. 16, 2028
Debt Instrument, Interest Rate, Stated Percentage	3.73%
3.88% note, due May 15, 2029 [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	May 15, 2029
Debt Instrument, Interest Rate, Stated Percentage	3.88%
3.25% due April 30, 2032 [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Apr. 30, 2032
Debt Instrument, Interest Rate, Stated Percentage	3.25%
3.48% note, due May 31, 2038 [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	May 31, 2038
Debt Instrument, Interest Rate, Stated Percentage	3.48%
Uncollateralized Senior Note Due November Two Thousand Thirty Eight [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Nov. 30, 2038
Debt Instrument, Interest Rate, Stated Percentage	3.58%
Uncollateralized Senior Note Due August Two Thousand Thirty Nine [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Aug. 20, 2039
Debt Instrument, Interest Rate, Stated Percentage	3.98%
Uncollateralized Senior Note Due December Two Thousand Thirty Four [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date	Dec. 20, 2034
Debt Instrument, Interest Rate, Stated Percentage	2.98%
Uncollateralized Senior Note Due July Two Thousand Thirty Five
Debt Instrument [Line Items]
Debt instrument, maturity date	Jul. 15, 2035
Debt Instrument, Interest Rate, Stated Percentage	3.00%
Uncollateralized Senior Note Due August Two Thousand Thirty Five
Debt Instrument [Line Items]
Debt instrument, maturity date	Aug. 15, 2035
Debt Instrument, Interest Rate, Stated Percentage	2.96%
Equipment Security Note
Debt Instrument [Line Items]
Debt instrument, maturity date	Sep. 29, 2031
Debt Instrument, Interest Rate, Stated Percentage	2.46%

Long-Term Debt - Additional Inf

Long-Term Debt - Additional Information (Detail) - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Document Period End Date		Sep. 30, 2021
Long-term debt including current maturities		$ 522,500	$ 523,000
Debt Instrument, Unused Borrowing Capacity, Amount		$ 310,000
Uncollateralized Senior Note Due December Two Thousand Thirty Four [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		2.98%
Term Note Due January Two Thousand Twenty [Member]
Debt Instrument [Line Items]
Long-term debt including current maturities		$ 70,000	70,000
3.48% note, due May 31, 2038 [Member]
Debt Instrument [Line Items]
Long-term debt including current maturities		50,000	50,000
3.25% note, due April 30, 2032 [Member]
Debt Instrument [Line Items]
Long-term debt including current maturities		70,000	$ 70,000
New York Life [Member]
Debt Instrument [Line Items]
Long-term debt including current maturities	[1]	140,000
Aggregated Unfunded Commitments [Member]
Debt Instrument [Line Items]
Long-term debt including current maturities		0
Aggregate Shelf Agreements [Member]
Debt Instrument [Line Items]
Long-term debt including current maturities		360,000
MetLife [Member]
Debt Instrument [Line Items]
Senior notes	[1]	150,000
Debt Instrument, Unused Borrowing Capacity, Amount	[1]	150,000
Prudential [Member]
Debt Instrument [Line Items]
Long-term debt including current maturities	[1]	220,000
Debt Instrument, Unused Borrowing Capacity, Amount	[1]	150,000
New York Life [Member]
Debt Instrument [Line Items]
Debt Instrument, Unused Borrowing Capacity, Amount	[1]	10,000
Maximum [Member] | Aggregate Shelf Agreements [Member]
Debt Instrument [Line Items]
Senior notes		670,000
Maximum [Member] | Prudential [Member]
Debt Instrument [Line Items]
Senior notes	[1]	370,000
Maximum [Member] | New York Life [Member]
Debt Instrument [Line Items]
Senior notes	[1]	$ 150,000
[1]	(1) The Prudential, MetLife and NYL Shelf Agreements expire in April 2023, May 2023 and November 2021, respectively.

Short-Term Borrowings (Details)

Short-Term Borrowings (Details) - USD ($)	1 Months Ended	3 Months Ended	9 Months Ended
	Feb. 28, 2021	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2020
Short-term Debt [Line Items]
Ratio of Indebtedness to Net Capital		0.65	0.65
Notional Amount of Nonderivative Instruments	$ 40,000,000	$ 70,000,000	$ 30,000,000
Line of Credit Facility, Remaining Borrowing Capacity		203,400,000	203,400,000
Short-term borrowing		$ 192,026,000	$ 192,026,000	$ 175,644,000
Short-term Debt, Weighted Average Interest Rate, at Point in Time		0.82%	0.82%	1.28%
Draws on letters of credit			$ 4,600,000
Financing Receivable, Revolving		$ 400,000,000	400,000,000
Revolving Line of Credit, Short-term
Short-term Debt [Line Items]
Financing Receivable, Revolving		$ 200,000,000	$ 200,000,000
Debt Instrument, Interest Rate, Stated Percentage		70.00%	70.00%
Revolving Line of Credit, Long-term
Short-term Debt [Line Items]
Financing Receivable, Revolving		$ 200,000,000	$ 200,000,000
Debt Instrument, Fee			0.09
Debt Instrument, Interest Rate, Stated Percentage		95.00%	95.00%
3.48% note, due May 31, 2038 [Member]
Short-term Debt [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		3.48%	3.48%
Committed Line of Credit Facility Two [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis			LIBOR rate, plus 0.75 percent
Committed Line of Credit Facility Three [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis			Lender's base rate, plus 0.75 percent
Committed Line of Credit Facility Five [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis			Lender's base rate, plus 0.85 percent
Committed Line of Credit Facility Four [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis			LIBOR rate, plus 1.125 percent
Committed Line of Credit Facility Six [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis			LIBOR rate, plus 1.75 percent
Committed Line of Credit Facility Seven [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis			LIBOR rate, plus 1.75 percent
Committed Line of Credit Facility Eight [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis			LIBOR rate, plus 1.75 percent
Committed Line of Credit Facility Nine [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis			LIBOR rate, plus 1.75 percent
Committed Line of Credit Facility One [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis			LIBOR rate, plus 0.75 percent
Revolving Credit Facility
Short-term Debt [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 400,000,000	$ 400,000,000
Interest Rate Swap Rate, Low Range [Member]
Short-term Debt [Line Items]
Fixed Swap Rate				0.20%
Interest Rate Swap Rate, High Range [Member]
Short-term Debt [Line Items]
Fixed Swap Rate		0.17%	0.17%	0.205%

Leases (Details)

Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Lease Disclosure [Abstract]
Operating Lease, Right-of-Use Asset	$ 9,602	$ 11,194
Operating Lease, Liability, Current	1,725	1,747
Operating Lease, Liability, Noncurrent	8,380	9,872
Total Operating and Finance Lease Liabilities	$ 10,105	$ 11,619

Leases Leases - Lease Cost Addi

Leases Leases - Lease Cost Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Lease, Cost [Abstract]
Operating Lease, Cost	[1]	$ 515	$ 627	$ 1,553	$ 1,882
[1]	(1) Includes short-term leases and variable lease costs, which are immaterial

Leases Leases - Right of Use As

Leases Leases - Right of Use Asset and Lease Liability Balance Sheet Classification Additional Information (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Leases - Right of Use Asset and Lease Liability Balance Sheet Classification [Abstract]
Operating Lease, Right-of-Use Asset	$ 9,602	$ 11,194
Operating Lease, Liability, Current	1,725	1,747
Operating Lease, Liability, Noncurrent	8,380	9,872
Total Operating and Finance Lease Liabilities	$ 10,105	$ 11,619

Leases Leases - Weighted Averag

Leases Leases - Weighted Average Remaining Lease Term Additional Information (Details)	Sep. 30, 2021	Dec. 31, 2020
Leases - Weighted Average Remaining Lease term Additional Information [Abstract]
Operating Lease, Weighted Average Discount Rate, Percent	3.80%	3.80%
Operating Lease, Weighted Average Remaining Lease Term	8 years 6 months 14 days	8 years 8 months 12 days

Leases Leases - Cash Flow Addit

Leases Leases - Cash Flow Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Leases - Cash Flow Additional Information [Abstract]
Operating Cash Flow from Operating Leases	$ 1,399	$ 1,435

Leases Leases - Schedule of Fut

Leases Leases - Schedule of Future Maturities Additional Information (Details) $ in Thousands	Sep. 30, 2021USD ($)
Leases - Schedule of Future Maturities Additional Information [Abstract]
Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year	$ 597	[1]
Lessee, Operating Lease, Liability, to be Paid, Year One	1,845	[1]
Lessee, Operating Lease, Liability, Payments, Due Year Two	1,762	[1]
Lessee, Operating Lease, Liability, Payments, Due Year Three	1,607	[1]
Lessee, Operating Lease, Liability, Payments, Due	11,745	[1]
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	(1,640)
Operating Lease, Liability	10,105	[1]
Lessee Future Operating Lease Option Payments	2,100
Lessee, Operating Lease, Liability, Payments, Due Year Four	1,387	[1]
Lessee, Operating Lease, Liability, Payments, Due Year Five	951	[1]
Lessee, Operating Lease, Liability, to be Paid, after Year Five	$ 3,596	[1]
[1]	Operating lease payments include $2.1 million related to options to extend lease terms that are reasonably certain of being exercised.