Chesapeake Utilities (CPK) 10-K 26 Feb 20 2019 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2019	Feb. 20, 2020	Jun. 30, 2019
Cover page.
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2019
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 Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
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 Public Float			$ 1.5
Entity Common Stock, Shares Outstanding		16,407,017
Documents Incorporated by Reference	Portions of the Proxy Statement for the 2020 Annual Meeting of Stockholders are incorporated by reference in Part II and Part III, which Proxy Statement shall be filed with the Securities and Exchange Commission within 120 days after the end of registrant's fiscal year ended December 31, 2019 .
Entity Central Index Key	0000019745
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Amendment Flag	false

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Revenues
Regulated Energy	$ 343,006	$ 345,281	$ 326,310
Unregulated Energy	154,150	161,904	140,076
Other	(17,552)	(16,869)	(16,740)
Total operating revenues	479,604	490,316	449,646
Operating Expenses
Regulated Energy cost of sales	102,803	121,828	118,769
Unregulated Energy and other cost of sales	51,697	68,342	53,420
Operations	137,844	132,523	121,949
Cost, Maintenance	15,679	14,387	12,701
Gain from a settlement	(130)	(130)	(130)
Depreciation and amortization	45,423	40,220	36,386
Other taxes	20,001	18,303	16,821
Total operating expenses	373,317	395,473	359,916
Operating Income	106,287	94,843	89,730
Other expense, net	(1,830)	(603)	(2,204)
Interest charges	22,224	16,146	12,530
Income from Continuing Operations Before Income Taxes	82,233	78,094	74,996
Income Taxes on Continuing Operations	21,091	21,232	14,670
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent	61,142	56,862	60,326
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	(1,391)	(282)	(2,202)
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax	5,402
Net Income (Loss) Attributable to Parent	$ 65,153	$ 56,580	$ 58,124
Weighted Average Common Shares Outstanding:
Basic (in shares)	16,398,443	16,369,616	16,336,789
Diluted (in shares)	16,448,486	16,419,870	16,383,352
Basic Earnings Per Share of Common Stock:
Income (Loss) from Continuing Operations, Per Basic Share	$ 3.73	$ 3.48	$ 3.69
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share	0.24	(0.02)	(0.13)
Basic (in usd per share)	3.97	3.46	3.56
Earnings Per Share, Diluted [Abstract]
Income (Loss) from Continuing Operations, Per Diluted Share	3.72	3.47	3.68
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share	0.24	(0.02)
Diluted (in usd per share)	$ 3.96	$ 3.45	$ 3.55

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net Income	$ 65,153	$ 56,580	$ 58,124
Employee Benefits, net of tax:
Amortization of prior service cost, net of tax of $(20), $(22) and $(31), respectively	(57)	(55)	(46)
Net gain(loss), net of tax of $368, $(49), and $432, respectively	1,052	(108)	663
Cash Flow Hedges, net of tax:
Unrealized (loss) on commodity contract cash flow hedges, net of tax of $(176), $(555) and $(8), respectively	(434)	(1,371)	(11)
Total Other Comprehensive Income (Loss)	561	(1,534)	606
Comprehensive Income	$ 65,714	$ 55,046	$ 58,730

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Tax expense recognized on the amortization of prior service cost	$ (20,000)	$ (22,000)	$ (31,000)
Tax expense recognized on the net gain (loss)	368,000	(49,000)	432,000
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	$ (176,000)	$ (555,000)	$ (8,000)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Activities
Net Income	$ 65,153	$ 56,580	$ 58,124
Adjustments to reconcile net income to net operating cash:
Depreciation and amortization	45,900	40,802	36,599
Depreciation and accretion included in operations expenses	8,752	8,535	8,122
Deferred income taxes, net	24,476	21,226	11,085
Gain on sale of discontinued operations	(7,344)	0	0
Realized gain (loss) on sale of assets/commodity contracts	(4,135)	5,497	3,179
Unrealized loss (gain) on investments/commodity contracts	(1,595)	429	(1,001)
Employee benefits and compensation	1,985	856	1,577
Share-based compensation	4,279	2,813	2,490
Other, net	0	0	(750)
Changes in assets and liabilities:
Accounts receivable and accrued revenue	36,489	(16,311)	(19,506)
Propane inventory, storage gas and other inventory	8,227	2,107	(9,036)
Regulatory assets/liabilities, net	(7,812)	2,250	(2,855)
Prepaid expenses and other current assets	11,115	(7,421)	(7,001)
Accounts payable and other accrued liabilities	(62,021)	35,907	15,596
Income taxes receivable (payable)	(4,750)	(522)	8,110
Customer deposits and refunds	(1,811)	(596)	5,513
Accrued compensation	2,120	708	2,488
Other assets and liabilities, net	(16,064)	(35,498)	(2,645)
Net cash provided by operating activities	102,964	117,362	110,089
Investing Activities
Property, plant and equipment expenditures	(184,727)	(240,351)	(175,329)
Proceeds from sale of assets	427	782	708
Acquisitions, net of cash acquired	(23,988)	(16,654)	(11,945)
Proceeds from the sale of discontinued operations	22,871
Environmental expenditures	(1,170)	(625)	(329)
Net cash used in investing activities	(186,587)	(256,848)	(186,895)
Financing Activities
Common stock dividends	(24,693)	(22,043)	(19,928)
Issuance of stock for Dividend Reinvestment Plan	(721)	(706)	89
Proceeds from issuance of common stock, net of expenses	0	0	(10)	[1]
Payment, Tax Withholding, Share-based Payment Arrangement	(692)	(1,210)	(692)
Change in cash overdrafts due to outstanding checks	(1,174)	(5,943)	1,738
Net borrowings (repayments) under line of credit agreements	(45,913)	49,432	39,338
Proceeds from issuance of long-term debt	199,648	154,819	69,807
Repayment of long-term debt and finance lease obligation	(41,936)	(34,388)	(12,100)
Net cash provided by financing activities	84,519	139,961	78,242
Net Increase in Cash and Cash Equivalents	896	475	1,436
Cash and Cash Equivalents — Beginning of Period	6,089	5,614	4,178
Cash and Cash Equivalents — End of Period	$ 6,985	$ 6,089	$ 5,614
[1]	Represents capitalized legal fees associated with our September 22, 2016 public offering.

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment
Regulated Energy		$ 1,441,473	$ 1,297,416
Unregulated Energy		265,209	236,440
Other businesses and eliminations		39,850	34,585
Total property, plant and equipment		1,746,532	1,568,441
Less: Accumulated depreciation and amortization		(336,876)	(294,089)
Plus: Construction work in progress		54,141	79,168
Net property, plant and equipment		1,463,797	1,353,520
Current Assets
Cash and cash equivalents		6,985	6,089
Accounts receivable (less allowance for uncollectible accounts of $1,337 and $1,058, respectively)		49,562	53,837
Accrued revenue		20,846	22,640
Propane inventory, at average cost		5,824	9,791
Other inventory, at average cost		6,067	7,127
Regulatory assets		5,144	4,796
Storage gas prepayments		3,541	3,433
Income taxes receivable		20,050	15,300
Prepaid expenses		13,928	10,079
Derivative assets, at fair value		0	82
Other current assets		2,879	5,682
Disposal Group, Including Discontinued Operation, Assets, Current		0	52,681
Total current assets		134,826	191,537
Deferred Charges and Other Assets
Goodwill		32,668	21,568
Other intangible assets, net		8,129	3,850
Investments, at fair value		9,229	6,711
Operating Lease, Right-of-Use Asset		11,563
Regulatory assets		73,407	72,422
Receivables and other deferred charges		49,579	36,401
Disposal Group, Including Discontinued Operation, Assets, Noncurrent		0	7,662
Total deferred charges and other assets		184,575	148,614
Total Assets		1,783,198	1,693,671
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)		7,984	7,971
Additional paid-in capital		259,253	255,651
Retained earnings		300,607	261,530
Accumulated other comprehensive loss		(6,267)	(6,713)
Deferred compensation obligation		4,543	3,854
Treasury stock		(4,543)	(3,854)
Total stockholders’ equity		561,577	518,439
Long-term debt, net of current maturities		440,168	316,020
Total capitalization		1,001,745	834,459
Current Liabilities
Current portion of long-term debt		45,600	11,935
Short-term borrowing		247,371	294,458
Accounts payable		54,068	98,681
Customer deposits and refunds		30,939	32,620
Accrued interest		2,554	2,317
Dividends payable		6,644	6,060
Accrued compensation		16,236	13,923
Regulatory liabilities		5,991	7,883
Derivative liabilities, at fair value		1,844	1,604
Other accrued liabilities		12,077	10,081
Disposal Group, Including Discontinued Operation, Liabilities	[1]		48,672
Total current liabilities		423,324	528,234
Deferred Credits and Other Liabilities
Deferred income taxes		180,656	156,820
Regulatory liabilities		127,744	135,039
Environmental liabilities		6,468	7,638
Other pension and benefit costs		30,569	28,513
Operating Lease, Liability, Noncurrent		9,896
Operating Lease, Liability		11,601
Deferred investment tax credits and other liabilities		2,796	2,968
Total deferred credits and other liabilities		358,129	330,978
Commitments and Contingencies
Total Capitalization and Liabilities		$ 1,783,198	$ 1,693,671
[1]	(3) At December 31, 2018 , current liabilities were primarily comprised of $31.1 million of accounts payable, $13.3 million of derivative liabilities at fair value and $2.7 million of other accrued liabilities.

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Allowance for uncollectible accounts	$ 1,337	$ 1,058
Common stock, par value	$ 0.4867	$ 0.4867
Common stock, shares authorized	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

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - 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]
Beginning Balances at Dec. 31, 2016		$ 446,086	[1]	$ 7,935	$ 250,967		$ 192,062	$ (4,878)	$ 2,416	$ (2,416)
Beginning Balances, shares at Dec. 31, 2016	[1],[2]			16,303,499
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		58,124					58,124
Other comprehensive loss		606						606
Dividends		(21,045)					21,045
Proceeds from issuance of common stock, net of expenses		(10)	[3]	$ 0	(10)
Stock Issued During Period, Shares, New Issues				0
Stock Issued During The Period Value Retirement Savings Plan And Dividend Reinvestment Plan		735		$ 5	730
Stock Issued During The Period Shares Retirement Savings Plan And Dividend Reinvestment Plan				10,771
Share-based compensation		1,798	[4],[5]	$ 15	1,783
Share-based compensation, shares				30,172
Treasury stock activities		0							979	(979)
Ending Balances at Dec. 31, 2017		486,294	[1]	$ 7,955	253,470		229,141	(4,272)	3,395	(3,395)
Ending Balances, shares at Dec. 31, 2017	[1],[2]			16,344,442
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		56,580					56,580
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		(1,498)
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect							907	(907)
Other comprehensive loss		(1,534)						(1,534)
Dividends		(23,600)					23,600
Stock Issued During Period, Shares, Dividend Reinvestment Plan				0
Stock Issued During Period, Value, Dividend Reinvestment Plan		(3)		$ 0	(3)
Proceeds from issuance of common stock, net of expenses		0
Share-based compensation		2,200	[4],[5]	$ 16	2,184	[4],[5]
Share-based compensation, shares	[4],[5]			34,103
Treasury stock activities									459	(459)
Ending Balances at Dec. 31, 2018		518,439		$ 7,971	255,651		261,530	(6,713)	3,854	(3,854)
Ending Balances, shares at Dec. 31, 2018	[1],[2]			16,378,545
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		65,153
Prior Period Reclassification Adjustment							115	(115)
Other comprehensive loss		561						561
Dividends		(26,191)					26,191
Stock Issued During Period, Value, Dividend Reinvestment Plan		(3)			(3)
Proceeds from issuance of common stock, net of expenses		0
Share-based compensation		3,618	[4],[5]	$ 13	3,605	[4],[5]
Share-based compensation, shares	[4],[5]			25,231
Treasury stock activities									689	(689)
Ending Balances at Dec. 31, 2019		$ 561,577		$ 7,984	$ 259,253		$ 300,607	$ (6,267)	$ 4,543	$ (4,543)
Ending Balances, shares at Dec. 31, 2019	[1],[2]			16,403,776
[1]	Includes 95,329 , 97,053 and 90,961 shares at December 31, 2019 , 2018 and 2017
[2]	2,000,000 shares of pref erred st ock at $0.01 par value per share have been authorized. No shares have been issued or are outstanding; accordingly, no information has been included in the Consolidated Statements of Stockholders’ Equity.
[3]	Represents capitalized legal fees associated with our September 22, 2016 public offering.
[4]	Includes amounts for shares issued for directors’ compensation.
[5]	The shares issued under the SICP are net of shares withheld for employee taxes. For 2019 , 2018 and 2017 , we withheld 7,635 , 16,918 and 10,269 shares, respectively, for taxes.

Consolidated Statements of St_2

Consolidated Statements of Stockholders' Equity Consolidated Statements of Stockholders' Equity (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Stockholders' Equity [Abstract]
Preferred Stock, Shares Authorized	2,000,000	2,000,000
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Shares Held In Trust For Deferred Compensation Plan	95,329	97,053	90,961
Shares Issued Under Performance Incentive Plan Withheld For Employee Taxes	7,635	16,918	10,269

Organization and Basis of Prese

Organization and Basis of Presentation	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Organization and Basis of Presentation	O RGANIZATION AND B ASIS OF P RESENTATION Chesapeake Utilities, incorporated in 1947 in Delaware, is a diversified energy company engaged in regulated and unregulated energy businesses. Our regulated energy businesses consist of: (a) regulated natural gas distribution operations in central and southern Delaware, Maryland’s eastern shore and Florida; (b) regulated natural gas transmission operations on the Delmarva Peninsula, in Pennsylvania and in Florida; and (c) regulated electric distribution operations serving customers in northeast and northwest Florida. Our unregulated energy businesses primarily include: (a) propane operations in the Mid-Atlantic region and Florida; (b) our unregulated natural gas transmission/supply operation in central and eastern Ohio; (c) our CHP plant in Florida that generates electricity and steam; and (d) our subsidiary, based in Florida, that provides CNG and pipeline solutions, primarily to utilities and pipelines throughout the eastern United States. Our consolidated financial statements include the accounts of Chesapeake Utilities and its wholly-owned subsidiaries. We do not have any ownership interest in investments accounted for using the equity method or any interest in a variable interest entity. All intercompany accounts and transactions have been eliminated in consolidation. We have assessed and, if applicable, reported on subsequent events through the date of issuance of these consolidated financial statements. Where necessary to improve comparability, prior period amounts have been changed to conform to current period presentation. Beginning in the third quarter of 2019 , our management began executing a strategy to sell the operating assets of PESCO. In connection with this strategy, during the third and fourth quarter of 2019 , we reached agreements with four entities to sell PESCO's assets and contracts. These transactions closed during the fourth quarter of 2019. As a result of the sale, we have fully exited the natural gas marketing business, which provided natural gas management and supply services to commercial and industrial customers in Florida, Delaware, Maryland, Pennsylvania, Ohio and other states. Accordingly, PESCO’s historical financial results are reflected in our consolidated financial statements as discontinued operations, which required retrospective application to financial information for all periods presented. Refer to Note 4, Acquisitions and Divestitures for further information.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Summary of Significant Accounting Policies	S UMMARY OF S IGNIFICANT A CCOUNTING P OLICIES Use of Estimates The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates in measuring assets and liabilities and related revenues and expenses. These estimates involve judgments about various future economic factors that are difficult to predict and are beyond our control; therefore, actual results could differ from these estimates. As additional information becomes available, or actual amounts are determined, recorded estimates are revised. Consequently, operating results can be affected by revisions to prior accounting estimates. Property, Plant and Equipment Property, plant and equipment are stated at original cost less accumulated depreciation or fair value, if impaired. Costs include direct labor, materials and third-party construction contractor costs, allowance for funds used during construction ("AFUDC"), and certain indirect costs related to equipment and employees engaged in construction. The costs of repairs and minor replacements are charged to expense as incurred, and the costs of major renewals and betterments are capitalized. Upon retirement or disposition of property within the regulated businesses, the gain or loss, net of salvage value, is charged to accumulated depreciation. Upon retirement or disposition of property owned by the unregulated businesses, the gain or loss, net of salvage value, is charged to income. A summary of property, plant and equipment for continuing operations by classification as of December 31, 2019 and 2018 is provided in the following table: As of December 31, (in thousands) 2019 2018 Property, plant and equipment Regulated Energy Natural gas distribution - Delmarva Peninsula and Florida $ 705,095 $ 657,630 Natural gas transmission - Delmarva Peninsula, Pennsylvania and Florida 608,727 537,654 Electric distribution 127,651 102,133 Unregulated Energy Propane operations – Mid-Atlantic and Florida 141,841 123,632 Natural gas transmission and supply – Ohio 73,658 70,225 Electricity and steam generation 35,436 35,239 Mobile CNG and pipeline solutions 14,014 7,240 Other unregulated energy 104 104 Other 40,006 34,584 Total property, plant and equipment 1,746,532 1,568,441 Less: Accumulated depreciation and amortization (336,876 ) (294,089 ) Plus: Construction work in progress 54,141 79,168 Net property, plant and equipment $ 1,463,797 $ 1,353,520 Contributions or Advances in Aid of Construction Customer contributions or advances in aid of construction reduce property, plant and equipment, unless the amounts are refundable to customers. Contributions or advances may be refundable to customers after a number of years based on the amount of revenues generated from the customers or the duration of the service provided to the customers. Refundable contributions or advances are recorded initially as liabilities. Non-refundable contributions reduce property, plant and equipment at the time of such determination. As of December 31, 2019 and 2018 , the non-refundable contributions totaled $2.1 million and $2.8 million , respectively. AFUDC Some of the additions to our regulated property, plant and equipment include AFUDC, which represents the estimated cost of funds, from both debt and equity sources, used to finance the construction of major projects. AFUDC is capitalized in the applicable rate base for ratemaking purposes when the completed projects are placed in service. During the years ended December 31, 2019 and 2018 , AFUDC totaled $0.7 million and $1.9 million , respectively, which was reflected as a reduction of interest charges. During the year ended December 31, 2017 , AFUDC was not material. Leases We have entered into lease arrangements for office space, land, equipment, pipeline facilities and warehouses. These leases enable us to conduct our business operations in the regions in which we operate. Our operating leases are included in operating lease right-of-use assets, other accrued liabilities, and operating lease - liabilities in our consolidated balance sheets. Right-of-use assets represent our right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. Operating lease right-of-use assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. Leases with an initial term of 12 months or less are not recorded on our balance sheet; we recognize lease expense for these leases on a straight-line basis over the lease term. Our leases do not provide an implicit lease rate, therefore, we utilize our incremental borrowing rate, as the basis to calculate the present value of future lease payments, at lease commencement. Our incremental borrowing rate represents the rate that we would have to pay to borrow funds on a collateralized basis over a similar term and in a similar economic environment. We have lease agreements with lease and non-lease components. At the adoption of ASC 842, we elected not to separate non-lease components from all classes of our existing leases. The non-lease components have been accounted for as part of the single lease component to which they are related. See Note 15, Leases for additional information. Jointly-owned Pipelines Property, plant and equipment for our Florida natural gas transmission operation also included $6.7 million of assets, at December 31, 2019 and 2018 , which consist of the 16 -mile pipeline from the Duval/Nassau County line to Amelia Island in Nassau County, Florida, jointly owned with Peoples Gas. The amount included in property, plant and equipment represents Peninsula Pipeline’s 45 -percent ownership of this pipeline. Peninsula Pipeline's share of direct expenses for the jointly-owned pipeline are included in operating expenses of our consolidated statements of income. Accumulated depreciation for this pipeline totaled $1.5 million and $1.4 million , at December 31, 2019 and 2018 , respectively. In May 2018, Peninsula Pipeline announced a plan to construct a jointly-owned 26 -mile intrastate transmission pipeline in Nassau County, Florida with Seacoast Gas Transmission. Peninsula Pipeline's ownership will be 50 percent. The pipeline is expected to be placed in-service during the third quarter of 2020. Asset Impairment Evaluations We periodically evaluate whether events or circumstances have occurred, which indicate that other long-lived assets may not be fully recoverable. The determination of whether an impairment has occurred is based on an estimate of undiscounted future cash flows attributable to the asset, compared to the carrying value of the asset. When such events or circumstances are present, we record an impairment loss equal to the excess of the asset's carrying value over its fair value, if any. Depreciation and Accretion Included in Operations Expenses We compute depreciation expense for our regulated operations by applying composite, annual rates, as approved by the respective regulatory bodies. The following table shows the average depreciation rates used for regulated operations during the years ended December 31, 2019 , 2018 and 2017 : 2019 2018 2017 Natural gas distribution – Delmarva Peninsula 2.5% 2.5% 2.5% Natural gas distribution – Florida 2.6% 2.9% 2.9% Natural gas transmission – Delmarva Peninsula 2.6% 2.7% 2.8% Natural gas transmission – Florida 2.4% 2.3% 3.5% Electric distribution 3.4% 3.4% 3.4% For our unregulated operations, we compute depreciation expense on a straight-line basis over the following estimated useful lives of the assets: Asset Description Useful Life Propane distribution mains 10-37 years Propane bulk plants and tanks 10-40 years Propane equipment, meters and meter installations 5-33 years Measuring and regulating station equipment 5-37 years Natural gas pipelines 45 years Natural gas right of ways Perpetual CHP plant 30 years Natural gas processing equipment 20-25 years Office furniture and equipment 3-10 years Transportation equipment 4-20 years Structures and improvements 5-45 years Other Various We report certain depreciation and accretion in operations expense, rather than as a depreciation and amortization expense, in the accompanying consolidated statements of income in accordance with industry practice and regulatory requirements. Depreciation and accretion included in operations expense consists of the accretion of the costs of removal for future retirements of utility assets, vehicle depreciation, computer software and hardware depreciation, and other minor amounts of depreciation expense. For the years ended December 31, 2019 , 2018 and 2017 , we reported $8.8 million , $8.5 million and $8.1 million , respectively, of depreciation and accretion in operations expenses. Regulated Operations We account for our regulated operations in accordance with ASC Topic 980, Regulated Operations, which includes accounting principles for companies whose rates are determined by independent third-party regulators. When setting rates, regulators often make decisions, the economics of which require companies to defer costs or revenues in different periods than may be appropriate for unregulated enterprises. When this situation occurs, a regulated company defers the associated costs as regulatory assets on the balance sheet and records them as expense on the income statement as it collects revenues. Further, regulators can also impose liabilities upon a regulated company, for amounts previously collected from customers and for recovery of costs that are expected to be incurred in the future, as regulatory liabilities. If we were required to terminate the application of these regulatory provisions to our regulated operations, all such deferred amounts would be recognized in the statement of income at that time, which could have a material impact on our financial position, results of operations and cash flows. We monitor our regulatory and competitive environments to determine whether the recovery of our regulatory assets continues to be probable. If we determined that recovery of these assets is no longer probable, we would write off the assets against earnings. We believe that the provisions of ASC Topic 980, Regulated Operations, continue to apply to our regulated operations and that the recovery of our regulatory assets is probable. Revenue Recognition Revenues for our natural gas and electric distribution operations are based on rates approved by the PSC in each state in which they operate. Customers’ base rates may not be changed without formal approval by these commissions. The PSCs, however, have authorized our regulated operations to negotiate rates, based on approved methodologies, with customers that have competitive alternatives. Eastern Shore’s revenues are based on rates approved by the FERC. The FERC has also authorized Eastern Shore to negotiate rates above or below the FERC-approved maximum rates, which customers can elect as an alternative to FERC-approved maximum rates. For regulated deliveries of natural gas and electricity, we read meters and bill customers on monthly cycles that do not coincide with the accounting periods used for financial reporting purposes. We accrue unbilled revenues for natural gas and electricity delivered, but not yet billed, at the end of an accounting period to the extent that they do not coincide. We estimate the amount of the unbilled revenue by jurisdiction and customer class. All of our regulated natural gas and electric distribution operations have fuel cost recovery mechanisms, except for two utilities that provide only unbundled delivery service (Chesapeake Utilities' Central Florida Gas division and FPU's Indiantown division). These mechanisms allow us to adjust billing rates, without further regulatory approvals, to reflect changes in the cost of purchased fuel. Differences between the cost of fuel purchased and delivered are deferred and accounted for as either unrecovered fuel cost or amounts payable to customers. Generally, these deferred amounts are recovered or refunded within one year. We charge flexible rates to our natural gas distribution industrial interruptible customers who can use alternative fuels. Interruptible service imposes no contractual obligation to deliver or receive natural gas on a firm service basis. Our unregulated propane delivery businesses record revenue in the period the products are delivered and/or services are rendered for their bulk delivery customers. For propane customers with meters whose billing cycles do not coincide with our accounting periods, we accrue unbilled revenue for product delivered but not yet billed and bill customers at the end of an accounting period, as we do in our regulated energy businesses. Our Ohio natural gas transmission/supply operation recognizes revenues based on actual volumes of natural gas shipped using contractual rates based upon index prices that are published monthly. Eight Flags records revenues based on the amount of electricity and steam generated and sold to its customers. Our mobile compressed natural gas operation recognizes revenue for CNG services at the end of each calendar month for services provided during the month based on agreed upon rates for labor, equipment utilized, costs incurred for natural gas compression, miles driven, mobilization and demobilization fees. We report revenue taxes, such as gross receipts taxes, franchise taxes, and sales taxes, on a net basis. Cost of Sales Cost of sales includes the direct costs attributable to the products sold or services provided to our customers. These costs include primarily the variable commodity cost of natural gas, electricity and propane, costs of pipeline capacity needed to transport and store natural gas, transmission costs for electricity, costs to gather and process natural gas, costs to transport propane to/from our storage facilities or our mobile CNG equipment to customer locations, and steam and electricity generation costs. Depreciation expense is not included in cost of sales. Operations and Maintenance Expenses Operations and maintenance expenses include operations and maintenance salaries and benefits, materials and supplies, usage of vehicles, tools and equipment, payments to contractors, utility plant maintenance, customer service, professional fees and other outside services, insurance expense, minor amounts of depreciation, accretion of removal costs for future retirements of utility assets and other administrative expenses. Cash and Cash Equivalents Our policy is to invest cash in excess of operating requirements in overnight income-producing accounts. Such amounts are stated at cost, which approximates fair value. Investments with an original maturity of three months or less when purchased are considered cash equivalents. Accounts Receivable and Allowance for Doubtful Accounts Accounts receivable consist primarily of amounts due for sales of natural gas, electricity and propane and transportation and distribution services to customers. An allowance for doubtful accounts is recorded against amounts due based upon our collections experiences and an assessment of our customers’ inability or reluctance to pay. If circumstances change, our estimates of recoverable accounts receivable may also change. Circumstances which could affect such estimates include, but are not limited to, customer credit issues, natural gas, electricity and propane prices and general economic conditions. Accounts are written off when they are deemed to be uncollectible. Inventories We use the average cost method to value propane, materials and supplies, and other merchandise inventory. If market prices drop below cost, inventory balances that are subject to price risk are adjusted to their net realizable value. There was no lower-of-cost-or-net realizable value adjustment during 2019 , 2018 or 2017 . Goodwill and Other Intangible Assets Goodwill is not amortized but is tested for impairment at least annually, or more frequently if an event occurs or circumstances change that would more likely than not reduce the fair value of a reporting unit below its carrying value. We use a present value technique based on discounted cash flows to estimate the fair value of our reporting units. An impairment charge is recognized if the carrying value of a reporting unit’s goodwill exceeds its implied fair value. The testing of goodwill for 2019 , 2018 and 2017 indicated no goodwill impairment. Other intangible assets are amortized on a straight-line basis over their estimated economic useful lives. Other Deferred Charges Other deferred charges include primarily issuance costs associated with short-term borrowings. These charges are amortized over the life of the related short-term debt borrowings. Asset Removal Cost As authorized by the appropriate regulatory body (state PSC or FERC), we accrue future asset removal costs associated with utility property, plant and equipment even if a legal obligation does not exist. Such accruals are provided for through depreciation expense and are recorded with corresponding credits to regulatory liabilities or assets. When we retire depreciable utility plant and equipment, we charge the associated original costs to accumulated depreciation and amortization, and any related removal costs incurred are charged to regulatory liabilities or assets. The difference between removal costs recognized in depreciation rates and the accretion and depreciation expense recognized for financial reporting purposes is a timing difference between recovery of these costs in rates and their recognition for financial reporting purposes. Accordingly, these differences are deferred as regulatory liabilities or assets. In the rate setting process, the regulatory liability or asset is excluded from the rate base upon which those utilities have the opportunity to earn their allowed rates of return. The costs associated with our asset retirement obligations are either currently being recovered in rates or are probable of recovery in future rates. Pension and Other Postretirement Plans Pension and other postretirement plan costs and liabilities are determined on an actuarial basis and are affected by numerous assumptions and estimates, including the fair value of plan assets, estimates of the expected returns on plan assets, assumed discount rates, the level of contributions made to the plans, and current demographic and actuarial mortality data. We review annually the estimates and assumptions underlying our pension and other postretirement plan costs and liabilities with the assistance of third-party actuarial firms. The assumed discount rates, expected returns on plan assets and the mortality assumption are the factors that generally have the most significant impact on our pension costs and liabilities. The assumed discount rates, health care cost trend rates and rates of retirement generally have the most significant impact on our postretirement plan costs and liabilities. The discount rates are utilized principally in calculating the actuarial present value of our pension and postretirement obligations and net pension and postretirement costs. When estimating our discount rates, we consider high-quality corporate bond rates, such as the Prudential curve index and the FTSE Pension Discount curve, formerly the Citigroup yield curve, changes in those rates from the prior year and other pertinent factors, including the expected life of each of our plans and their respective payment options. The expected long-term rates of return on assets are utilized in calculating the expected returns on the plan assets component of our annual pension plan costs. We estimate the expected returns on plan assets of each of our plans by evaluating expected bond returns, asset allocations, the effects of active plan management, the impact of periodic plan asset rebalancing and historical performance. We also consider the guidance from our investment advisors in making a final determination of our expected rates of return on assets. We estimate the health care cost trend rates used in determining our postretirement net expense based upon actual health care cost experience, the effects of recently enacted legislation and general economic conditions. Our assumed rate of retirement is estimated based upon our annual reviews of participant census information as of the measurement date. The mortality assumption used for our pension and postretirement plans is reviewed periodically and is based on the actuarial table that best reflects the expected mortality of the plan participants. Income Taxes, Investment Tax Credit Adjustments and Tax-Related Contingency Deferred tax assets and liabilities are recorded for the income tax effect of temporary differences between the financial statement basis and tax basis of assets and liabilities and are measured using the enacted income tax rates in effect in the years in which the differences are expected to reverse. Deferred tax assets are recorded net of any valuation allowance when it is more likely than not that such income tax benefits will be realized. Investment tax credits on utility property have been deferred and are allocated to income ratably over the lives of the subject property. We account for uncertainty in income taxes in our consolidated financial statements only if it is more likely than not that an uncertain tax position is sustainable based on technical merits. Recognizable tax positions are then measured to determine the amount of benefit recognized in the consolidated financial statements. We recognize penalties and interest related to unrecognized tax benefits as a component of other income. We account for contingencies associated with taxes other than income when the likelihood of a loss is both probable and estimable. In assessing the likelihood of a loss, we do not consider the existence of current inquiries, or the likelihood of future inquiries, by tax authorities as a factor. Our assessment is based solely on our application of the appropriate statutes and the likelihood of a loss, assuming the proper inquiries are made by tax authorities. Financial Instruments Our propane operations enter into derivative transactions, such as swaps, put options and call options in order to mitigate the impact of wholesale price fluctuations on inventory valuation and future purchase commitments. These transactions may be designated as fair value hedges or cash flow hedges, if they meet all of the accounting requirements pursuant to ASC Topic 815, Derivatives and Hedging, and we elect to designate the instruments as hedges. If designated as a fair value hedge, the value of the hedging instrument, such as a swap, future, or put option, is recorded at fair value, with the effective portion of the gain or loss of the hedging instrument effectively reducing or increasing the value of the hedged item. If designated as a cash flow hedge, the value of the hedging instrument, such as a swap or call option, is recorded at fair value with the effective portion of the gain or loss of the hedging instrument being recorded in comprehensive income. The ineffective portion of the gain or loss of a hedge is recorded in earnings. If the instrument is not designated as a fair value or cash flow hedge, or it does not meet the accounting requirements of a hedge under ASC Topic 815, Derivatives and Hedging , it is recorded at fair value with all gains or losses being recorded directly in earnings. Our natural gas, electric and propane operations enter into agreements with suppliers to purchase natural gas, electricity, and propane for resale to our respective customers. Purchases under these contracts, as well as distribution and sales agreements with counterparties or customers, either do not meet the definition of a derivative, or qualify for “normal purchases and sales” treatment under ASC Topic 815 Derivatives and Hedging , and are accounted for on an accrual basis. Recently Adopted Accounting Standards Leases (ASC 842) - In February 2016, the FASB issued ASU 2016-02, Leases, which requires lessees to recognize leases on the balance sheet and disclose key information about leasing arrangements. The standard establishes a right of use model that requires a lessee to recognize a right of use asset and lease liability for all leases with a term greater than 12 months. The update also expands the required quantitative and qualitative disclosures surrounding leases. ASC 842 was subsequently amended by ASU No. 2018-01, Land Easement Practical Expedient for Transition to Topic 842 ; ASU No. 2018-10, Codification Improvements to Topic 842, Lease s; ASU No. 2018-11, Targeted Improvements ; and ASU No. 2019-01, Codification Improvements . We adopted ASU 2016-02 and the related amendments on January 1, 2019, and used the optional transition method for all existing leases. The optional transition method enabled us to adopt the new standard as of the beginning of the period of adoption and did not require restatement of prior period financial information. As a result, prior period financial information was not recast and continues to be reported under the accounting guidance effective during those periods. At adoption, we elected the following practical expedients: (1) the ‘package of practical expedients,’ pursuant to which we did not need to reassess our prior conclusions about lease identification, lease classification and initial direct costs, (2) the ‘use-of-hindsight’ practical expedient, which allowed us to use hindsight in assessing impairment of our existing land easements, (3) the creation of an accounting policy for short-term leases resulting in lease payments being recorded as an expense on a straight-line basis over the lease term, and (4) the aggregation, rather than separation, of the lease and non-lease components for all leases. See Note 15, Leases, for additional information with respect to the impact of the adoption of the lease accounting guidance and the disclosures required by ASU 2016-02 and the related amendments. Compensation - Stock Compensation (ASC 718) - In June 2018, the FASB issued ASU 2018-07, Improvements to Nonemployee Share-Based Payment Accounting , which expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. We adopted ASU 2018-07 on January 1, 2019. Implementation of this new standard did not have a material impact on our financial position or results of operations. Recent Accounting Standards Yet to be Adopted Financial Instruments - Credit Losses (ASC 326) - In June 2016, the FASB issued ASU 2016-13, Measurement of Credit Losses on Financial Instruments , which changes how entities account for credit losses for most financial assets and certain other instruments, and subsequent guidance which served to clarify or amend the original standard. ASU 2016-13 and the related amendments require entities to estimate lifetime expected credit losses for trade receivables and to provide additional disclosure related to credit losses. ASU 2016-13 will be effective for our annual and interim financial statements beginning January 1, 2020 and is not expected to have a material impact on our financial position or results of operations. Intangibles - Goodwill (ASC 350) - In January 2017, the FASB issued ASU 2017-04, Simplifying the Test for Goodwill Impairment , which simplifies how an entity is required to test goodwill for impairment by eliminating Step 2 from the goodwill impairment test. ASU 2017-04 will be effective for our annual and interim financial statements beginning January 1, 2020, although early adoption is permitted. The amendments included in this ASU are to be applied prospectively, and are not expected to have a material impact on our financial position or results of operations. Fair Value Measurement (ASC 820) - In August 2018, the FASB issued ASU 2018-13, Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement , which removes, modifies and adds certain disclosure requirements on fair value measurements in ASC 820. ASU 2018-13 will be effective for our annual and interim financial statements beginning January 1, 2020, and since the changes only impact disclosures, will not have a material impact on our financial position or results of operations.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Earnings Per Share	3. E ARNINGS P ER S HARE The following table presents the calculation of our basic and diluted earnings per share for the years ended December 31: For the Year Ended December 31, 2019 2018 2017 (in thousands, except shares and per share data) Calculation of Basic Earnings Per Share: Income from Continuing Operations $ 61,142 $ 56,862 $ 60,326 Income/(Loss) from Discontinued Operations 4,011 (282 ) (2,202 ) Net Income $ 65,153 $ 56,580 $ 58,124 Weighted average shares outstanding 16,398,443 16,369,616 16,336,789 Earnings Per Share from Continuing Operations $ 3.73 $ 3.48 $ 3.69 Earnings/(Loss) Per Share from Discontinued Operations 0.24 (0.02 ) (0.13 ) Basic Earnings Per Share $ 3.97 $ 3.46 $ 3.56 Calculation of Diluted Earnings Per Share: Reconciliation of Denominator: Weighted average shares outstanding — Basic 16,398,443 16,369,616 16,336,789 Effect of dilutive securities — Share-based compensation 50,043 50,254 46,563 Adjusted denominator — Diluted 16,448,486 16,419,870 16,383,352 Earnings Per Share from Continuing Operations $ 3.72 $ 3.47 $ 3.68 Earnings/(Loss) Per Share from Discontinued Operations 0.24 (0.02 ) (0.13 ) Diluted Earnings Per Share $ 3.96 $ 3.45 $ 3.55

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Acquisitions	A CQUISITIONS AND DIVESTITURES Acquisition of Elkton Gas Company In December 2019, we entered into an agreement with SJI to acquire its subsidiary, Elkton Gas Company, which provides natural gas distribution service to approximately 7,000 residential and commercial customers within a franchised area of Cecil County, Maryland. Upon completion of the transaction, Elkton Gas Company will become our wholly-owned subsidiary. The acquisition, which is expected to close in the second half of 2020, is subject to approval by the Maryland PSC. Elkton Gas Company's territory is contiguous to our franchised service territory in Cecil County, Maryland and it will continue to operate out of its existing office with the same local personnel. Acquisitions in 2019 In December 2019, Sharp acquired certain propane operating assets of Boulden which provides propane distribution service to approximately 5,200 customers in Delaware, Maryland and Pennsylvania, for approximately $24.6 million , net of cash acquired. Additionally, the purchase price included $0.2 million of working capital. We recorded contingent consideration of $0.6 million related to the seller's adherence to various provisions contained in the contract through the first anniversary of the transaction closing. We accounted for the purchase of the operating assets of Boulden as a business combination within our Unregulated Energy segment. In connection with this acquisition, we recorded $8.3 million in property, plant and equipment, $5.1 million in intangible assets associated with customer relationships and non-compete agreements and $11.2 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 that will be finalized at the end of the measurement period. Contributions to our operating revenues and operating income as a result of this acquisition for the year ended December 31, 2019 can be found in the table below. Acquisitions in 2018 In December 2018, Marlin Gas Services acquired certain operating assets of Marlin Gas Transport, a supplier of CNG and pipeline solutions, primarily to utilities and pipelines. Marlin Gas Services provides temporary hold services, pipeline integrity services, emergency services for damaged pipelines and specialized gas services for customers who have unique requirements. These services are provided by a highly trained staff of drivers and maintenance technicians who safely perform these functions throughout the eastern United States. Marlin Gas Services maintains a fleet of steel tube CNG trailers, composite CNG trailers, mobile compression equipment and an internally-developed patented regulator system which allows for delivery of over 7,000 Dts/d of natural gas. In December 2018, Sharp acquired certain propane operating assets and customers of Ohl, which provided propane distribution service to approximately 2,500 residential and commercial customers in Pennsylvania. We accounted for the purchases of the operating assets of Marlin Gas Transport and Ohl, which totaled approximately $18.2 million , as business combinations within our Unregulated Energy segment. Goodwill of $4.8 million , related to the Marlin Gas Transport acquisition, and $1.5 million , associated with the Ohl acquisition, were initially recorded at the close of these transactions. In 2019, we recorded a reduction to the purchase price for Ohl of $0.2 million upon completing our verification of the assets purchased. The purchase price adjustment was recorded as a reduction in our property, plant and equipment balance. Due to the timing of these acquisitions, the revenue and operating income from these acquisitions in 2018 were immaterial. For the year ended December 31, 2019 , these acquisitions generated the following operating revenue and income: For the Year Ended December 31, 2019 Operating Revenues Operating Income (in thousands) Marlin Gas Services $ 5,702 $ 1,500 Ohl propane acquisition $ 1,662 $ 385 Boulden acquisition $ 550 $ 239 Divestiture of PESCO In September of 2019, we initiated a plan to sell a majority of the assets of PESCO, our natural gas marketing subsidiary. This was done in an effort to enable us to focus on the strategies that support our core energy delivery business. During the fourth quarter of 2019, we executed four separate transactions associated with the sale of PESCO’s assets and contracts: • PESCO’s Florida retail operations were sold to Gas South. The initial closing for the transaction was completed in November 2019 with subsequent closings occurring in December 2019 . • PESCO’s other non-Florida retail operations a n d contracts were sold to UET in October 2019. • PESCO’s Mid-Atlantic wholesale contracts and Chesapeake Utilities’ Delaware division, Maryland division and Sandpiper Energy asset management agreements were sold to NJRES in October 2019. • PESCO's producer services portfolio was sold to DFS in December 2019. We received a total of $22.9 million in cash consideration from the aforementioned buyers that was inclusive of working capital of $8.0 million from UET. We recognized a pre-tax gain of $7.3 million in connection with the closing of these transactions during the fourth quarter of 2019. The final working capital true up associated with the sale of assets and contracts to UET will be finalized in the first quarter of 2020. As a result of the sales agreements, we began to report PESCO as discontinued operations during the third quarter of 2019 and excluded PESCO's performance from continuing operations for all periods presented and classified its assets and liabilities as held for sale. The assets and liabilities of PESCO are presented as current and noncurrent assets and liabilities of a business held for sale in the consolidated balance sheets. Additionally, amounts for operating revenues and costs of sales which had previously been eliminated in consolidation related to intercompany sales and purchases have been grossed up and are now reflected as a component of operating revenues and costs of sales for all periods presented. We have recast these amounts because, upon completion of the sales transactions, we will continue to provide and receive services from the buyers. A summary of discontinued operations presented in the consolidated statements of income includes the following: For the Year Ended December 31, (in thousands) 2019 2018 2017 Operating revenues (1) $ 161,289 $ 258,713 $ 184,519 Cost of sales (1) 157,646 252,111 182,307 Other operating expenses 5,222 6,825 4,522 Operating loss (1,579 ) (223 ) (2,310 ) Interest and other expense 315 297 253 Loss from Discontinued Operations before income taxes (1,894 ) (520 ) (2,563 ) Gain on sale of Discontinued Operations 7,344 — — Income tax (benefit) / expense 1,439 (238 ) (361 ) Gain / (Loss) from Discontinued Operations, Net of Tax $ 4,011 $ (282 ) $ (2,202 ) (1) Included in operating revenues and cost of sales for the years ended December 31, 2019 , 2018 and 2017 , is $19.8 million , $31.5 million and $16.6 million respectively, representing amounts which had been previously eliminated in consolidation related to intercompany activity that will continue with the buyers after the disposition of the assets of PESCO. As a result of the disposition of the assets and contracts of PESCO, there were no assets or liabilities classified as held for sale at December 31, 2019. The assets and liabilities of the discontinued operations classified as held for sale in the consolidated balance sheet at December 31, 2018 include the following: As of (in thousands) December 31, 2018 Property, plant and equipment $ 1,242 Less: accumulated depreciation (206 ) Net property, plant and equipment (1) 1,036 Current assets (2) 52,681 Deferred charges and other assets (1) 6,626 Assets of Discontinued Operations held for sale $ 60,343 Current liabilities (3) $ 48,672 Liabilities of Discontinued Operations held for sale $ 48,672 Net assets $ 11,671 (1) These balances have been combined within the consolidated balance sheets to arrive at noncurrent assets held for sale. (2) At December 31, 2018 , current assets were primarily comprised of $31.1 million of accounts receivable, $13.1 million of derivative assets at fair value, $4.9 million of accrued revenue and $3.2 million of storage gas prepayments. (3) At December 31, 2018 , current liabilities were primarily comprised of $31.1 million of accounts payable, $13.3 million of derivative liabilities at fair value and $2.7 million of other accrued liabilities. We have elected not to separately disclose discontinued operations on the consolidated statements of cash flows. The following table summarizes significant statements of cash flows data related to the discontinued operations of PESCO: For the Year Ended December 31, (in thousands) 2019 2018 2017 Depreciation and amortization $ 477 $ 582 $ 213 Property, plant and equipment expenditures — 115 11,766 Deferred income taxes (125 ) 1,088 (1,515 ) Realized / (loss) gain on commodity contracts (2,161 ) 5,002 4,911 Our Delmarva Peninsula natural gas distribution operations had asset management agreements with PESCO to manage their natural gas transportation and storage capacity. The agreements were effective as of April 1, 2017, and each expires on March 31, 2020. As a result of the sale of the assets of PESCO, effective October 1, 2019, these agreements are now managed by NJRES through the remainder of the contract term. In addition to the asset management agreements, Eastern Shore had several firm transportation and capacity arrangements with PESCO which were included in the assets sold to UET. Eastern Shore will continue to fulfill these arrangements throughout the remainder of their contractual term. These agreements currently have expiration dates of March 31, 2020 and November 30, 2021.

Revenue Recognition Revenue Rec

Revenue Recognition Revenue Recognition (Notes)	12 Months Ended
	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customer [Text Block]	R EVENUE R ECOGNITION 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 revenue from continuing operations by major source based on product and service type for the years ended December 31, 2019 and 2018 : For the Year Ended December 31, 2019 For the Year Ended December 31, 2018 (in thousands) Regulated Energy Unregulated Energy Other and Eliminations Total Regulated Energy Unregulated Energy Other and Eliminations Total Energy distribution Delaware natural gas division $ 62,659 $ — $ — $ 62,659 $ 70,338 $ — $ — $ 70,338 Florida natural gas division 28,485 — — 28,485 25,341 — — 25,341 FPU electric distribution 77,416 — — 77,416 79,803 — — 79,803 FPU natural gas distribution 82,418 — — 82,418 81,118 — — 81,118 Maryland natural gas division 22,517 — — 22,517 24,172 — — 24,172 Sandpiper natural gas/propane operations 19,068 — — 19,068 22,088 — — 22,088 Total energy distribution 292,563 — — 292,563 302,860 — — 302,860 Energy transmission Aspire Energy — 32,493 — 32,493 — 35,407 — 35,407 Eastern Shore 72,924 — — 72,924 64,248 — — 64,248 Peninsula Pipeline 16,453 — — 16,453 11,927 — — 11,927 Total energy transmission 89,377 32,493 — 121,870 76,175 35,407 — 111,582 Energy generation Eight Flags — 16,749 — 16,749 — 17,302 — 17,302 Propane operations Propane delivery operations — 107,964 — 107,964 — 123,603 — 123,603 Energy delivery services Marlin Gas Services — 5,702 — 5,702 — 121 — 121 Other and eliminations Eliminations (38,934 ) (10,407 ) (18,080 ) (67,421 ) (33,754 ) (16,486 ) (17,522 ) (67,762 ) Other — 1,649 528 2,177 — 1,957 653 2,610 Total other and eliminations (38,934 ) (8,758 ) (17,552 ) (65,244 ) (33,754 ) (14,529 ) (16,869 ) (65,152 ) Total operating revenues (1) $ 343,006 $ 154,150 $ (17,552 ) $ 479,604 $ 345,281 $ 161,904 $ (16,869 ) $ 490,316 (1) Total operating revenues for the year ended December 31, 2019, 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 $0.2 million and $0.3 million for our Regulated and Unregulated Energy segments, respectively, for the year ended December 31, 2018. The sources of other revenues include revenue from alternative revenue programs related to revenue normalization for Maryland division and Sandpiper and late fees. Regulated Energy Segment The businesses within our Regulated Energy segment are regulated utilities whose operations and customer contracts are subject to rates approved by the respective state PSC or the FERC. Our energy distribution operations deliver natural gas or electricity to customers, and we bill the customers for both the delivery of natural gas or electricity and the related commodity, where applicable. In most jurisdictions, our customers are also required to purchase the commodity from us, although certain customers in some jurisdictions may purchase the commodity from a third-party retailer (in which case we provide delivery service only). We consider the delivery of natural gas or electricity and/or the related commodity sale as one performance obligation because the commodity and its delivery are highly interrelated with two-way dependency on one another. Our performance obligation is satisfied over time as natural gas or electricity is delivered and consumed by the customer. We recognize revenues based on monthly meter readings, which are based on the quantity of natural gas or electricity used and the approved rates. We accrue unbilled revenues for natural gas and electricity that have been delivered, but not yet billed, at the end of an accounting period, to the extent that billing and delivery do not coincide. Revenues for Eastern Shore are based on rates approved by the FERC. The FERC has also authorized Eastern Shore to negotiate rates above or below the FERC-approved maximum rates, which customers can elect as an alternative to the FERC-approved maximum rates. Eastern Shore's services can be firm or interruptible. Firm services are offered on a guaranteed basis and are available at all times unless prevented by force majeure or other permitted curtailments. Interruptible customers receive service only when there is available capacity or supply. Our performance obligation is satisfied over time as we deliver natural gas to the customers' locations. We recognize revenues based on capacity used or reserved and the fixed monthly charge. Peninsula Pipeline is engaged in natural gas intrastate transmission to third-party customers and certain affiliates in the State of Florida. Our performance obligation is satisfied over time as the natural gas is transported to customers. We recognize revenue based on rates approved by the Florida PSC and the capacity used or reserved. We accrue unbilled revenues for transportation services provided and not yet billed at the end of an accounting period. Unregulated Energy Segment Revenues generated from the Unregulated Energy segment are not subject to any federal, state, or local pricing regulations. Aspire Energy primarily sources gas from hundreds of conventional producers and performs gathering and processing functions to maintain the quality and reliability of its gas for its wholesale customers. Aspire Energy's performance obligation is satisfied over time as natural gas is delivered to its customers. Aspire Energy recognizes revenue based on the deliveries of natural gas at contractually agreed upon rates (which are based upon an established monthly index price and a monthly operating fee, as applicable). For natural gas customers, we accrue unbilled revenues for natural gas that has been delivered, but not yet billed, at the end of an accounting period, to the extent that billing and delivery do not coincide with the end of the accounting period. Eight Flags' CHP plant, which is located on land leased from Rayonier, produces three sources of energy: electricity, steam and heated water. Rayonier purchases the steam (unfired and fired) and heated water, which are used in Rayonier’s production facility. Our electric distribution operation purchases the electricity generated by the CHP plant for distribution to its customers. Eight Flags' performance obligation is satisfied over time as deliveries of heated water, steam and electricity occur. Eight Flags recognizes revenues over time based on the amount of heated water, steam and electricity generated and delivered to its customers. For our propane operations, we recognize revenue based upon customer type and service offered. Generally, for propane bulk delivery customers (customers without meters) and wholesale sales, our performance obligation is satisfied when we deliver propane to the customers' locations (point-in-time basis). We recognize revenue from these customers based on the number of gallons delivered and the price per gallon at the point-in-time of delivery. For our propane delivery customers with meters, we satisfy our performance obligation over time when we deliver propane to customers. We recognize revenue over time based on the amount of propane consumed and the applicable price per unit. For propane delivery metered customers, we accrue unbilled revenues for propane that has been delivered, but not yet billed, at the end of an accounting period, to the extent that billing and delivery do not coincide with the end of the accounting period. Marlin Gas Services provides mobile CNG and pipeline solutions primarily to utilities and pipelines. Marlin Gas Services provides temporary hold services, pipeline integrity services, emergency services for damaged pipelines and specialized gas services for customers who have unique requirements. Marlin Gas Services' performance obligations are comprised of the compression of natural gas, mobilization of CNG equipment, utilization of equipment and on-site CNG support. Our performance obligations for the compression of natural gas, utilization of mobile CNG equipment and for the on-site CNG staff support are satisfied over time when the natural gas is compressed, equipment is utilized or as our staff provide support services to our customers. Our performance obligation for the mobilization of CNG equipment is satisfied at a point-in-time when the equipment is delivered to the customer project location. We recognize revenue for CNG services at the end of each calendar month for services provided during the month based on agreed upon rates for equipment utilized, costs incurred for natural gas compression, miles driven, mobilization and demobilization 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 consolidated balance sheets. The balances of our trade receivables, contract assets, and contract liabilities as of December 31, 2019 and 2018 were as follows: Trade Receivables Contract Assets (Noncurrent) Contract Liabilities (Current) (in thousands) Balance at 12/31/2018 $ 52,140 $ 2,614 $ 480 Balance at 12/31/2019 47,430 3,465 589 Increase (decrease) $ (4,710 ) $ 851 $ 109 Our trade receivables are included in accounts receivable in the consolidated balance sheets. Our non-current contract assets are included in receivables and other deferred charges in the consolidated balance sheet and 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 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 years ended December 31, 2019 and 2018, we recognized revenue of $1.0 million and $0.7 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 December 31, 2019 are expected to be recognized as follows: (in thousands) 2020 2021 2022 2023 2024 2025 and thereafter Eastern Shore and Peninsula Pipeline $ 37,307 $ 34,000 $ 27,034 $ 21,608 $ 19,385 $ 194,868 Natural gas distribution operations 3,996 4,058 5,100 4,916 4,681 37,149 FPU electric distribution 566 566 566 566 566 1,100 Total revenue contracts with remaining performance obligations $ 41,869 $ 38,624 $ 32,700 $ 27,090 $ 24,632 $ 233,117 Practical expedients

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Segment Information	S EGMENT I NFORMATION We use the management approach to identify operating segments. We organize our business around differences in regulatory environment and/or products or services, 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 our mobile compressed natural gas 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, PESCO's results, previously reported in the Unregulated Energy segment, are reflected in discontinued operations. See Note 4, Acquisitions and Divestitures for additional details regarding the divestiture of PESCO. 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 information about our reportable segments. For the Year Ended December 31, 2019 2018 2017 (in thousands) Operating Revenues, Unaffiliated Customers Regulated Energy $ 340,857 $ 343,313 $ 323,972 Unregulated Energy 138,747 147,003 125,674 Total operating revenues, unaffiliated customers $ 479,604 $ 490,316 $ 449,646 Intersegment Revenues (1) Regulated Energy $ 2,149 $ 1,968 $ 2,338 Unregulated Energy 15,403 14,902 14,402 Other businesses 528 652 774 Total intersegment revenues $ 18,080 $ 17,522 $ 17,514 Operating Income Regulated Energy $ 86,584 $ 79,215 $ 74,584 Unregulated Energy 19,939 17,124 14,941 Other businesses and eliminations (236 ) (1,496 ) 205 Operating Income 106,287 94,843 89,730 Other expense, net (1,830 ) (603 ) (2,204 ) Interest charges 22,224 16,146 12,530 Income from Continuing Operations before Income Taxes $ 82,233 $ 78,094 $ 74,996 Income Taxes on Continuing Operations 21,091 21,232 14,670 Income from Continuing Operations 61,142 56,862 60,326 Loss from Discontinued Operations, Net of tax (1,391 ) (282 ) (2,202 ) Gain on sale of Discontinued Operations, Net of tax 5,402 — — Net Income $ 65,153 $ 56,580 $ 58,124 Depreciation and Amortization Regulated Energy $ 35,227 $ 31,876 $ 28,554 Unregulated Energy 10,129 8,263 7,741 Other businesses and eliminations 67 81 91 Total depreciation and amortization $ 45,423 $ 40,220 $ 36,386 Capital Expenditures Regulated Energy $ 130,604 $ 235,912 $ 159,011 Unregulated Energy 60,034 38,585 14,424 Other businesses 8,348 8,364 5,902 Total capital expenditures $ 198,986 $ 282,861 $ 179,337 (1) All significant intersegment revenues are billed at market rates and have been eliminated from consolidated revenues. As of December 31, 2019 2018 Identifiable Assets (1) Regulated Energy segment $ 1,434,066 $ 1,345,805 Unregulated Energy segment (1) 296,810 245,702 Other businesses and eliminations 52,322 41,821 Total identifiable assets (1) $ 1,783,198 $ 1,633,328 (1) 2018 balance excludes assets held for sale related to the sale of assets and contracts for PESCO.

Supplemental Cash Flow Disclosu

Supplemental Cash Flow Disclosures	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Supplemental Cash Flow Disclosures	S UPPLEMENTAL C ASH F LOW D ISCLOSURES Cash paid for interest and income taxes during the years ended December 31, 2019 , 2018 and 2017 were as follows: For the Year Ended December 31, 2019 2018 2017 (in thousands) Cash paid for interest $ 22,611 $ 16,741 $ 12,420 Cash paid for income taxes, net of refunds $ 3,221 $ 477 $ (4,114 ) Non-cash investing and financing activities during the years ended December 31, 2019 , 2018 , and 2017 were as follows: For the Year Ended December 31, 2019 2018 2017 (in thousands) Capital property and equipment acquired on account, but not paid for as of December 31 $ 13,470 $ 39,402 $ 15,457 Common stock issued under the SICP $ 1,691 $ 2,006 $ 1,127 Capital lease obligation $ — $ 1,310 $ 2,070

Derivative Instruments

Derivative Instruments	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Derivative Instruments	8. D ERIVATIVE I NSTRUMENTS 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. 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. Aspire Energy 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. As of December 31, 2019 and 2018 , our natural gas and electric distribution operations did not have any outstanding derivative contracts. PESCO's Derivative Instruments As discussed in Note 4, Acquisitions and Divestitures , during the fourth quarter of 2019, we sold PESCO's assets and contracts to UET, NJRES, Gas South, and DFS and, therefore, no longer have natural gas futures and contracts recorded in our consolidated financial statements. The gains and losses associated with PESCO's financial instruments are reflected as discontinued operations in the consolidated statements of income and PESCO's assets and liabilities are reflected as held-for-sale in the consolidated balance sheets. Volume of Derivative Activity As of December 31, 2019 , the volume of our open commodity derivative contracts were as follows: Business unit Commodity Quantity hedged (in millions) Designation Longest expiration date of hedge Sharp Propane (gallons) 9.9 Cash flows hedges June 2022 Sharp entered into futures and swap agreements to mitigate the risk of fluctuations in wholesale propane index prices associated with the propane volumes expected to be purchased during the heating season. Under the futures and swap agreements, Sharp will receive the difference between (i) the index prices (Mont Belvieu prices in December 2019 through June 2022) 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 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 $1.5 million from accumulated other comprehensive income to earnings during the next 12-month period ending December 31, 2020. 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 MTM relative to maintenance margin requirements. We currently maintain a broker margin account for Sharp, with the balance related to the account is as follows: (in thousands) Balance Sheet Location December 31, 2019 December 31, 2018 Sharp Other Current Assets $ 2,317 $ 2,173 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. As discussed in Note 4, Acquisitions and Divestitures , during the fourth quarter of 2019, we sold PESCO's assets and contracts. PESCO's derivative assets and liabilities are reflected as assets and liabilities held-for-sale in the consolidated balance sheet as of December 31, 2018. Fair values of the derivative contracts recorded in the consolidated balance sheets as of December 31, 2019 and 2018 are as follows: Derivative Assets Fair Value as of (in thousands) Balance Sheet Location December 31, 2019 December 31, 2018 Derivatives designated as fair value hedges Propane put options Derivative assets, at fair value $ — $ 71 Derivatives designated as cash flow hedges Propane swap agreements Derivative assets, at fair value — 11 Total Derivative Assets $ — $ 82 Derivative Liabilities Fair Value as of (in thousands) Balance Sheet Location December 31, 2019 December 31, 2018 Derivatives designated as cash flow hedges Propane swap agreements Derivative liabilities, at fair value $ 1,844 $ 1,604 Total Derivative Liabilities $ 1,844 $ 1,604 The effects of gains and losses from derivative instruments are as follows: Amount of Gain (Loss) on Derivatives: Location of Gain (Loss) on Derivatives For the Year Ended December 31, (in thousands) 2019 2018 2017 Derivatives not designated as hedging instruments Realized gain on forward contracts and options (1) Revenue $ — $ — $ 112 Propane swap agreements Cost of sales — (13 ) 8 Derivatives designated as fair value hedges Put/Call option Cost of sales — — (9 ) Derivatives designated as cash flow hedges Propane swap agreements Cost of sales 1,520 (647 ) 1,607 Propane swap agreements Other comprehensive income (loss) (253 ) (2,773 ) 487 Natural gas swap contracts Other comprehensive income (loss) (63 ) 200 986 Natural gas futures contracts Other comprehensive income (loss) (294 ) 532 (1,476 ) Total $ 910 $ (2,701 ) $ 1,715 (1) All of the realized and unrealized gain (loss) on forward contracts represented the effect of trading activities for Xeron on our consolidated statement of income. As of December 31, 2019 and 2018, we did not have any material fair value hedges.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Fair Value of Financial Instruments	F AIR V ALUE OF F INANCIAL I NSTRUMENTS 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 and 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 December 31, 2019 and 2018 , respectively: Fair Value Measurements Using: As of December 31, 2019 Fair Value Quoted Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) (in thousands) Assets: Investments—equity securities $ 27 $ 27 $ — $ — Investments—guaranteed income fund 803 — — 803 Investments—mutual funds and other 8,399 8,399 — — Total investments 9,229 8,426 — 803 Derivative assets — — — — Total assets $ 9,229 $ 8,426 $ — $ 803 Liabilities: Derivative liabilities $ 1,844 $ — $ 1,844 $ — Fair Value Measurements Using: As of December 31, 2018 Fair Value Quoted Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) (in thousands) Assets: Investments—equity securities $ 22 $ 22 $ — $ — Investments—guaranteed income fund 686 — — 686 Investments—mutual funds and other 6,003 6,003 — — Total investments 6,711 6,025 — 686 Derivative assets (1) 82 — 82 — Total assets $ 6,793 $ 6,025 $ 82 $ 686 Liabilities: Derivative liabilities (1) $ 1,604 $ — $ 1,604 $ — (1) As discussed in Note 4, Acquisitions and Divestitures , during the fourth quarter of 2019, we sold PESCO's assets and contracts. PESCO's derivative assets and liabilities are reflected as assets held-for-sale in the consolidated balance sheet as of December 31, 2018. The following table sets forth the summary of the changes in the fair value of Level 3 investments for the years ended December 31, 2019 and 2018 : For the Year Ended December 31, 2019 2018 (in thousands) Beginning Balance $ 686 $ 648 Purchases and adjustments 131 68 Transfers/disbursements (29 ) (41 ) Investment income 15 11 Ending Balance $ 803 $ 686 Investment income from the Level 3 investments is reflected in other expense, net in the consolidated statements of income. At December 31, 2019 and 2018 , 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, 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 short maturities and because interest rates approximate current market rates (Level 3 measurement). At December 31, 2019 , long-term debt, which includes the current maturities but excludes debt issuance cost, had a carrying value of $486.6 million , compared to the estimated fair value of $505.0 million . At December 31, 2018 , long-term debt, which includes the current maturities but excludes finance lease obligations and debt issuance costs, had a carrying value of $327.2 million , compared to a fair value of $323.8 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. See Note 17, Employee Benefit Plans, for fair value measurement information related to our pension plan assets.

Investments

Investments	12 Months Ended
	Dec. 31, 2019
Investments [Abstract]
Investments	I NVESTMENTS The investment balances at December 31, 2019 and 2018 , consisted of the following: As of December 31, (in thousands) 2019 2018 Rabbi trust (associated with the Non-Qualified Deferred Compensation Plan) $ 9,202 $ 6,689 Investments in equity securities 27 22 Total $ 9,229 $ 6,711 We classify these investments as trading securities and report them at their fair value. For the years ended December 31, 2019 , 2018 and 2017 , we recorded net unrealized gains of $1.6 million , net unrealized losses of $0.4 million , and net unrealized gains of $1.0 million , respectively in other income (expense) in the consolidated statements of income related to these investments. For the investments 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.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Goodwill and Other Intangible Assets	G OODWILL AND O THER I NTANGIBLE A SSETS The carrying value of goodwill from continuing operations as of December 31, 2019 and 2018 was as follows: As of December 31, (in thousands) 2019 2018 Goodwill Regulated Energy Florida Natural Gas Distribution (1) $ 3,353 $ 3,353 Unregulated Energy (2) Mid-Atlantic Propane Operations (3) 13,299 2,147 Florida Propane Operations 1,188 1,188 Aspire Energy 10,120 10,120 Marlin Gas Services 4,708 4,760 Total Goodwill $ 32,668 $ 21,568 (1) Florida Natural Gas Distribution includes Chesapeake Utilities' Central Florida Gas division, FPU and FPU's Indiantown and Fort Meade divisions. (2) As discussed in Note 4, Acquisitions and Divestitures , during the fourth quarter of 2019, we sold PESCO's assets and contracts. The goodwill balance for PESCO is reflected as assets held-for-sale in the consolidated balance sheet as of December 31, 2018. (3) Mid-Atlantic Propane Operations goodwill balance includes $11.2 million recognized as a result of the purchase of the operating assets of Boulden in December 2019. The annual impairment testing for 2019 and 2018 indicated no impairment of goodwill. The carrying value and accumulated amortization of intangible assets subject to amortization as of December 31, 2019 and 2018 are as follows: As of December 31, 2019 2018 (in thousands) Gross Carrying Amount Accumulated Amortization Gross Carrying Amount Accumulated Amortization Customer relationships (1) $ 9,391 $ 3,463 $ 4,801 $ 3,066 Non-Compete agreements (1) (2) 2,252 451 1,793 202 Patents 452 118 452 — Other 270 204 270 198 Total $ 12,365 $ 4,236 $ 7,316 $ 3,466 (1) The customer relationship and non-compete agreements amounts includes $4.6 million and $0.5 million , respectively, recorded as a result of the purchase of the operating assets of Boulden in December 2019. (2) As discussed in Note 4, Acquisitions and Divestitures , during the fourth quarter of 2019, we sold PESCO's assets and contracts. Intangible assets for PESCO are reflected as assets held-for-sale in the consolidated balance sheet as of December 31, 2018 and amortization is reflected as discontinued operations in the consolidated statements of income. The customer relationships, non-compete agreements, patents and other intangible assets acquired in the purchases of the operating assets of several companies are being amortized over a weighted average of 11 years. Amortization expense of intangible assets for the year ended December 31, 2019 was $0.8 million and $0.4 million for both years ended December 31, 2018 and 2017 . Amortization expense of intangible assets is expected to be $1.2 million for the years 2020 and 2021, $0.9 million for the year 2022 and $0.8 million for the years 2023 and 2024.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income Taxes	I NCOME T AXES We file a consolidated federal income tax return. Income tax expense allocated to our subsidiaries is based upon their respective taxable incomes and tax credits. State income tax returns are filed on a separate company basis in most states where we have operations and/or are required to file. Our state returns for tax years after 2014 are subject to examination. At December 31, 2019 , the 2015 through 2018 federal income tax returns are under examination, and no report has been issued at this time. We had a net operating loss for federal income tax purposes as of December 31, 2019 totaling $3.0 million . We will have a federal net operating loss totaling $12.2 million for 2018 upon the settlement of the Internal Revenue Service audit described above. We did not have a federal net operating loss for tax year 2017. For state income tax purposes, we had net operating losses in various states of $54.7 million and $60.1 million as of December 31, 2019 and 2018 , respectively, almost all of which will expire in 2038. Excluding net operating losses from discontinued operations we have recorded deferred tax assets of $5.5 million and $2.0 million related to state net operating loss carry-forwards at December 31, 2019 and 2018 , respectively, but we have not recorded a valuation allowance to reduce the future benefit of the tax net operating losses because we believe they will be fully utilized. Federal Tax Reform On December 22, 2017, President Trump signed into law the TCJA. Substantially all of the provisions of the TCJA were effective for taxable years beginning on or after January 1, 2018. The provisions that significantly impacted us include the reduction of the corporate federal income tax rate from 35 percent to 21 percent . Our federal income tax expense for periods beginning on January 1, 2018 are based on the new federal corporate income tax rate. The TCJA included changes to the Internal Revenue Code, which materially impacted our 2017 financial statements. ASC 740, Income Taxes, requires recognition of the effects of changes in tax laws in the period in which the law is enacted. ASC 740 requires deferred tax assets and liabilities to be measured at the enacted tax rate expected to apply when temporary differences are to be realized or settled. During 2018, we completed the assessment of the impact of accounting for certain effects of the TCJA. At the date of enactment in 2017, we re-measured deferred income taxes based upon the new corporate tax rate. See Note 19, Rates and Other Regulatory Activities, for further discussion of the TCJA's impact on our regulated businesses. In 2018, we elected early adoption of ASU 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income. Accordingly, we reclassified stranded tax effects resulting from the TCJA from accumulated other comprehensive loss to retained earnings, related to our employee benefit plans and commodity contracts cash flow hedges. The following tables provide: (a) the components of income tax expense in 2019 , 2018 , and 2017 ; (b) the reconciliation between the statutory federal income tax rate and the effective income tax rate for 2019 , 2018 , and 2017 from continuing operations; and (c) the components of accumulated deferred income tax assets and liabilities at December 31, 2019 and 2018 . For the Year Ended December 31, 2019 2018 2017 (in thousands) Current Income Tax Expense Federal $ (2,271 ) $ 48 $ 2,046 State (492 ) 581 610 Other (47 ) (47 ) (71 ) Total current income tax expense (benefit) (2,810 ) 582 2,585 Deferred Income Tax Expense (1) Property, plant and equipment 25,910 19,189 8,181 Deferred gas costs 79 (1,435 ) 2,002 Pensions and other employee benefits (454 ) 446 180 FPU merger-related premium cost and deferred gain (278 ) (528 ) (1,148 ) Net operating loss carryforwards (3,776 ) (183 ) 193 Other 2,420 3,161 2,677 Total deferred income tax expense 23,901 20,650 12,085 Income Tax Expense from Continuing Operations 21,091 21,232 14,670 Income Tax Expense (benefit) from Discontinued Operations 1,439 (238 ) (361 ) Total Income Tax $ 22,530 $ 20,994 $ 14,309 (1) Includes $4.7 million , $3.5 million , and $0.9 million of deferred state income taxes for the years 2019 , 2018 and 2017 , respectively. For the Year Ended December 31, 2019 2018 2017 (in thousands) Reconciliation of Effective Income Tax Rates for Continuing Operations Federal income tax expense (1) $ 17,246 $ 16,491 $ 26,249 State income taxes, net of federal benefit 5,088 4,057 2,000 ESOP dividend deduction (173 ) (158 ) (257 ) Revaluation of deferred tax assets and liabilities — — (14,299 ) Other (1,070 ) 842 977 Total Income Tax Expense for Continuing Operations $ 21,091 $ 21,232 $ 14,670 Effective Income Tax Rate for Continuing Operations (2) 25.65 % 27.19 % 19.56 % (1) Federal income taxes were calculated at 21 percent for 2019 and 2018 and 35 percent for 2017. (2) The effective tax rate for 2017 includes the impact of the revaluation of deferred tax assets and liabilities for our unregulated businesses due to implementation of the TCJA. As of December 31, 2019 2018 (in thousands) Deferred Income Taxes Deferred income tax liabilities: Property, plant and equipment $ 173,466 $ 153,423 Acquisition adjustment 6,969 8,896 Loss on reacquired debt 220 32 Deferred gas costs 1,223 1,139 Natural gas conversion costs 4,956 3,987 Storm reserve liability 10,316 97 Other 1,456 2,544 Total deferred income tax liabilities 198,606 170,118 Deferred income tax assets: Pension and other employee benefits 3,818 3,711 Environmental costs 1,486 1,710 Net operating loss carryforwards 5,523 2,010 Self-insurance 146 151 Storm reserve liability 96 — Other 6,881 5,716 Total deferred income tax assets 17,950 13,298 Deferred Income Taxes Per Consolidated Balance Sheets $ 180,656 $ 156,820

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Long-Term Debt	L ONG - TERM D EBT Our outstanding long-term debt is shown below: As of December 31, (in thousands) 2019 2018 FPU secured first mortgage bonds: 9.08% bond, due June 1, 2022 $ 7,990 $ 7,986 Uncollateralized Senior Notes: 5.50% note, due October 12, 2020 2,000 4,000 5.93% note, due October 31, 2023 12,000 15,000 5.68% note, due June 30, 2026 20,300 23,200 6.43% note, due May 2, 2028 6,300 7,000 3.73% note, due December 16, 2028 18,000 20,000 3.88% note, due May 15, 2029 50,000 50,000 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 — 2.98% note, due December 20, 2034 70,000 — Term Note due January 21, 2020 — 30,000 Term Note due February 28, 2020 30,000 — Promissory notes — 26 Finance lease obligations — 1,310 Less: debt issuance costs (822 ) (567 ) Total long-term debt 485,768 327,955 Less: current maturities (45,600 ) (11,935 ) Total long-term debt, net of current maturities $ 440,168 $ 316,020 Annual maturities Annual maturities and principal repayments of long-term debt are as follows: Year 2020 2021 2022 2023 2024 Thereafter Total (in thousands) Payments $ 45,600 $ 13,600 $ 25,100 $ 20,600 $ 17,600 $ 364,100 $ 486,600 Shelf Agreements We have entered into Shelf Agreements with Prudential, MetLife and NYL who are under no obligation to purchase any unsecured debt. The Prudential Shelf Agreement totaling $150.0 million was entered into in October 2015 and we issued $70.0 million of 3.25% unsecured debt in April 2017. The Prudential Shelf Agreement was amended in September 2018 to increase the borrowing capacity back to $150.0 million , and in August 2019, we issued $100.0 million of 3.98% unsecured debt. In January 2020, we submitted a request for Prudential to purchase $50 million of our unsecured debt which was accepted and confirmed by Prudential. The Shelf notes will bear interest at the rate of 3.00% per annum and the proceeds received from the issuance will be used to reduce short-term borrowings under our revolving credit facility, lines of credit and/or to fund capital expenditures. The closing of the issuance of the Shelf Notes is expected to occur on or before July 15, 2020. The NYL Shelf Agreement totaling $100.0 million was entered into in March 2017 and we issued unsecured debt totaling $100.0 million during 2018. The NYL Shelf Agreement was amended in November 2018 to provide additional borrowing capacity of $50.0 million . As of December 31, 2019 , we had not requested that MetLife purchase unsecured senior debt under the MetLife Shelf Agreement, which we entered into in March 2017. In February 2020, we submitted a request for NYL to purchase $40.0 million of our unsecured debt which was accepted and confirmed by NYL. The Shelf notes will bear interest at the rate of 2.96% per annum and the proceeds received from the issuance will be used to reduce short-term borrowings under our revolving credit facility, lines of credit and/or to fund capital expenditures. The closing of the issuance of the Shelf Notes is expected to occur on or before August 14, 2020. The following table summarizes our shelf agreements at December 31, 2019: (in thousands) Total Borrowing Capacity Less Amount of Debt Issued Less Unfunded Commitments Remaining Borrowing Capacity Shelf Agreement Prudential Shelf Agreement (1) $ 220,000 $ (170,000 ) $ — $ 50,000 MetLife Shelf Agreement 150,000 — — 150,000 NYL Shelf Agreement (2) 150,000 (100,000 ) — 50,000 Total $ 520,000 $ (270,000 ) $ — $ 250,000 (1) As described above, in January 2020, we requested and Prudential accepted our request to purchase $50.0 million of our unsecured debt. (2) As described above, in February 2020, we requested and NYL accepted our request to purchase $40.0 million of our unsecured debt. 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. Term Notes In December 2018, we issued a $30 million unsecured term note through PNC Bank N.A. with a maturity date of January 21, 2020. This note was paid off in December 2019 utilizing the proceeds from the issuance of uncollateralized senior notes discussed below. In January 2019, we issued a $30.0 million unsecured term note through Branch Banking and Trust Company, with a maturity date of February 28, 2020. The interest rate, at December 31, 2019 , was 2.46% , which equals the one-month LIBOR rate plus 75 basis points. As of December 31, 2019 , this term note is included in the current maturities of long-term debt. Secured First Mortgage Bonds We guaranteed FPU’s first mortgage bonds, which are secured by a lien covering all of FPU’s property. FPU’s first mortgage bonds contain a restriction that limits the payment of dividends by FPU to an amount less than the sum of $2.5 million plus FPU’s consolidated net income accrued on and after January 1, 1992. As of December 31, 2019 , FPU’s cumulative net income base was $168.1 million , offset by restricted payments of $37.6 million , leaving $130.5 million of available dividend capacity. The dividend restrictions in FPU’s first mortgage bonds resulted in approximately $38.8 million of the net assets of our consolidated subsidiaries being restricted at December 31, 2019 . This represents approximately 6.92% of our consolidated net assets. Other than the dividend restrictions associated with FPU’s first mortgage bonds, there are no legal, contractual or regulatory restrictions on the net assets of our subsidiaries. Uncollateralized Senior Notes In December 2019, we issued $70.0 million of 2.98% uncollateralized senior notes to four financial institutions. We used the proceeds to pay off the $30 million PNC Term Note described above, reduce our short-term borrowing amount and to finance our purchase of certain propane operating assets of Boulden. All of our uncollateralized Senior Notes require periodic principal and interest payments as specified in each note. They also contain various restrictions. The most stringent restrictions state that we must maintain equity of at least 40.0 percent of total capitalization, and the fixed charge coverage ratio must be at least 1.2 times. The most recent Senior Notes issued since September 2013 also contain a restriction that we must maintain an aggregate net book value in our regulated business assets of at least 50.0 percent of our consolidated total assets. Failure to comply with those covenants could result in accelerated due dates and/or termination of the Senior Note agreements. Certain uncollateralized Senior Notes contain a “restricted payments” covenant as defined in the respective note agreements. The most restrictive covenants of this type are included within the 5.93% Senior Note, due October 31, 2023. The covenant provides that we cannot pay or declare any dividends or make any other restricted payments in excess of the sum of $10.0 million , plus our consolidated net income accrued on and after January 1, 2003. As of December 31, 2019 , the cumulative consolidated net income base was $509.5 million , offset by restricted payments of $227.5 million , leaving $282.0 million of cumulative net income free of restrictions. As of December 31, 2019 , we are in compliance with all of our debt covenants.

Short-Term Borrowing

Short-Term Borrowing	12 Months Ended
	Dec. 31, 2019
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Short-Term Borrowing	S HORT - TERM B ORROWINGS At December 31, 2019 and 2018 , we had $ 247.4 million and $294.5 million , respectively, of short-term borrowings outstanding at the weighted average interest rates of 2.62 percent and 3.44 percent , respectively. We have an aggregate of $370.0 million in credit lines comprised of four unsecured bank credit facilities with four financial institutions, with $220.0 million in total available credit, and a Revolver with five participating Lenders totaling $150.0 million . All of these facilities expire in October 2020 . We incurred commitment fees of $0.1 million in 2019 , 2018 and 2017 . The following table summarizes our short-term borrowing facilities information at December 31, 2019 and 2018 . Outstanding borrowings at (in thousands) Total Facility LIBOR Based Interest Rate December 31, 2019 December 31, 2018 Available at December 31, 2019 Bank Credit Facility Committed revolving credit facility A $ 55,000 plus 0.75 percent $ 55,000 $ 25,000 $ — Committed revolving credit facility B 80,000 plus 0.75 percent 57,150 65,431 22,850 Committed revolving credit facility C 45,000 plus 0.75 percent 42,040 34,672 2,960 Committed revolving credit facility D 40,000 plus 0.85 percent 40,000 40,000 — Committed revolving credit facility E (2) 150,000 plus 1.125 percent 50,000 125,000 100,000 Total short term credit facilities $ 370,000 $ 244,190 $ 290,103 $ 125,810 Book overdrafts (1) 3,181 4,355 Total short-term borrowing $ 247,371 $ 294,458 (1) If presented, these book overdrafts would be funded through the bank revolving credit facilities. (2) This committed revolving credit facility includes a restriction that our short-term borrowings, excluding any borrowings under the committed revolving credit facility, shall not exceed $250.0 million . We are authorized by our Board of Directors to borrow up to $370.0 million of short-term debt, as required, from these short-term lines of credit. These bank credit facilities 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. The availability of funds under our credit facilities is subject to conditions specified in the respective credit agreements, 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 our revolving credit facilities to maintain, at the end of each fiscal year, a funded indebtedness ratio of no greater than 65 percent . As of December 31, 2019 , we are in compliance with all of our debt covenants.

Leases

Leases	12 Months Ended
	Dec. 31, 2019
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Leases	L EASES 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 all 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 December 31, 2019 , 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 which preclude our ability to pay dividends, obtain financing or enter into additional leases. As of December 31, 2019 , 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: Year Ended December 31, ( in thousands) Classification 2019 2018 Operating lease cost (1) Operations expense $ 2,577 $ 3,339 Finance lease cost: Amortization of lease assets Depreciation and amortization 650 1,451 Interest on lease liabilities Interest expense 5 49 Net lease cost $ 3,232 $ 4,839 (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 consolidated balance sheet at December 31, 2019 : (in thousands) Balance sheet classification Amount Assets Operating lease assets Operating lease right-of-use assets $ 11,563 Liabilities Current Operating lease liabilities Other accrued liabilities 1,705 Noncurrent Operating lease liabilities Operating lease - liabilities 9,896 Total lease liabilities $ 11,601 The following table presents our weighted-average remaining lease term and weighted-average discount rate for our operating leases at December 31, 2019 : December 31, 2019 Weighted-average remaining lease term ( in years ) Operating leases 8.88 Weighted-average discount rate Operating leases 3.8 % The following table presents additional information related to cash paid for amounts included in the measurement of lease liabilities included in our consolidated statements of cash flows as of December 31, 2019 and 2018 : Year Ended December 31, (in thousands) 2019 2018 Operating cash flows from operating leases $ 2,230 $ 2,759 Operating cash flows from finance leases $ 5 $ 49 Financing cash flows from finance leases $ 650 $ 1,451 The following table presents the future undiscounted maturities of our operating leases at December 31, 2019 and for each of the next five years and thereafter: (in thousands) Operating Leases (1) 2020 $ 2,104 2021 1,866 2022 1,716 2023 1,719 2024 1,463 Thereafter 4,916 Total lease payments 13,784 Less: Interest 2,183 Present value of lease liabilities $ 11,601 (1) Operating lease payments include $3.7 million related to options to extend lease terms that are reasonably certain of being exercised.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
Accumulated Other Comprehensive Income (Loss)	S TOCKHOLDERS' E QUITY Accumulated Other Comprehensive (Loss) Defined benefit pension and postretirement plan items, unrealized gains (losses) of our propane swap agreements, call options and natural gas futures and swap contracts, designated as commodity contracts cash flow hedges, are the components of our accumulated comprehensive income (loss). In 2018, we elected early adoption of ASU 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income. Accordingly, we reclassified stranded tax effects resulting from the TCJA from accumulated other comprehensive loss to retained earnings, related to our employee benefit plans and commodity contract cash flow hedges. The following table presents the changes in the balance of accumulated other comprehensive loss for the years ended December 31, 2019 and 2018 . All amounts in the following tables are presented net of tax. Defined Benefit Pension and Postretirement Plan Items Commodity Contract Cash Flow Hedges Total (in thousands) As of December 31, 2017 $ (4,743 ) $ 471 $ (4,272 ) Other comprehensive loss before reclassifications (602 ) (3,130 ) (3,732 ) Amounts reclassified from accumulated other comprehensive income 439 1,759 2,198 Net current-period other comprehensive loss (163 ) (1,371 ) (1,534 ) Stranded tax reclassification to retained earnings (1,022 ) 115 (907 ) As of December 31, 2018 (5,928 ) (785 ) (6,713 ) Other comprehensive income/(loss) before reclassifications (872 ) 2,161 1,289 Amounts reclassified from accumulated other comprehensive income/(loss) 1,867 (2,595 ) (728 ) Net current-period other comprehensive income/(loss) 995 (434 ) 561 Prior-year reclassification — (115 ) (115 ) As of December 31, 2019 $ (4,933 ) $ (1,334 ) $ (6,267 ) The following table presents amounts reclassified out of accumulated other comprehensive income (loss) for the years ended December 31, 2019 , 2018 and 2017 . Deferred gains and losses of our commodity contracts cash flow hedges are recognized in earnings upon settlement. For the Year Ended December 31, (in thousands) 2019 2018 2017 Amortization of defined benefit pension and postretirement plan items: Prior service cost (1) $ 77 $ 77 $ 77 Net gain (1) (2,600 ) (579 ) (636 ) Total before income taxes (2,523 ) (502 ) (559 ) Income tax benefit (4) 656 63 223 Net of tax $ (1,867 ) $ (439 ) $ (336 ) Gains and losses on commodity contracts cash flow hedges Propane swap agreements (2) $ 1,520 $ (647 ) $ 1,607 Natural gas swaps (2)(3) 7 197 (822 ) Natural gas futures (2)(3) 2,096 (2,010 ) (456 ) Total before income taxes 3,623 (2,460 ) 329 Income tax impact (4) (1,028 ) 701 (159 ) Net of tax $ 2,595 $ (1,759 ) $ 170 Total reclassifications for the period $ 728 $ (2,198 ) $ (166 ) (1) These amounts are included in the computation of net periodic benefits. See Note 17 , Employee Benefit Plans , for additional details. (2) These amounts are included in the effects of gains and losses from derivative instruments. See Note 8, Derivative Instruments , for additional details. (3) PESCO's results are reflected as discontinued operations in our consolidated statements of income. (4) The income tax benefit is included in income tax expense in the accompanying consolidated statements of income.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2019
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Employee Benefit Plans	E MPLOYEE B ENEFIT P LANS We measure the assets and obligations of the defined benefit pension plans and other postretirement benefits plans to determine the plans’ funded status as of the end of the year. We record as a component of other comprehensive income/loss or a regulatory asset the changes in funded status that occurred during the year that are not recognized as part of net periodic benefit costs. Defined Benefit Pension Plans We sponsor three defined benefit pension plans: the Chesapeake Pension Plan, the FPU Pension Plan and the Chesapeake unfunded supplemental executive retirement pension plan ("SERP"). The Chesapeake Pension Plan, a qualified plan, was closed to new participants, effective January 1, 1999, and was frozen with respect to additional years of service and additional compensation, effective January 1, 2005. Benefits under the Chesapeake Pension Plan were based on each participant’s years of service and highest average compensation, prior to the freezing of the plan. Active participants on the date the Chesapeake Pension Plan was frozen were credited with two additional years of service. In 2019, we executed a de-risking strategy for the Chesapeake Pension Plan. As a result, during the fourth quarter of 2019, we purchased annuities for those retirees currently receiving monthly payments and offered lump-sum payments to terminated vested employees. Accordingly, the pension settlement expense associated with the de-risking strategy allocated to our Regulated Energy operations was recorded as regulatory assets or deferred pending regulatory approval authorizing recovery through rates. The remaining portion of the pension settlement expense totaling $0.7 million was recorded in other expense in our consolidated statement of income which reflected the amount allocated to our Unregulated Energy operations or was deemed not recoverable through the regulatory process. The FPU Pension Plan, a qualified plan, covers eligible FPU non-union employees hired before January 1, 2005 and union employees hired before the respective union contract expiration dates in 2005 and 2006. Prior to the FPU merger, the FPU Pension Plan was frozen with respect to additional years of service and additional compensation, effective December 31, 2009. The Chesapeake SERP, a nonqualified plan, is comprised of two sub-plans. The first sub-plan was frozen with respect to additional years of service and additional compensation as of December 31, 2004. Benefits under the Chesapeake SERP for the first sub-plan were based on each participant’s years of service and highest average compensation, prior to the freezing of the plan. Active participants on the date the Chesapeake SERP was frozen were credited with two additional years of service. The second sub- plan provides fixed payments for several executives who joined the Company as a result of an acquisition and whose agreements with the Company provided for this benefit. The unfunded liability for all three plans at both December 31, 2019 and 2018 , is included in the other pension and benefit costs liability in our consolidated balance sheets. The following schedules set forth the funded status at December 31, 2019 and 2018 and the net periodic cost for the years ended December 31, 2019 , 2018 and 2017 for the Chesapeake and FPU Pension Plans as well as the Chesapeake SERP: Chesapeake Pension Plan FPU Pension Plan Chesapeake At December 31, 2019 2018 2019 2018 2019 2018 (in thousands) Change in benefit obligation: Benefit obligation — beginning of year $ 10,712 $ 11,443 $ 59,377 $ 64,664 $ 2,285 $ 2,428 Interest cost 375 384 2,452 2,339 74 83 Actuarial loss (gain) 1,443 (610 ) 6,508 (4,739 ) 159 (74 ) Effect of settlement (5,833 ) — — — — — Benefits paid (483 ) (505 ) (3,033 ) (2,887 ) (361 ) (152 ) Benefit obligation — end of year 6,214 10,712 65,304 59,377 2,157 2,285 Change in plan assets: Fair value of plan assets — beginning of year 8,649 9,350 43,601 48,396 — — Actual return on plan assets 1,180 (647 ) 7,978 (3,113 ) — — Employer contributions 1,117 451 1,157 1,205 361 152 Effect of settlement (5,833 ) — — — — Benefits paid (483 ) (505 ) (3,033 ) (2,887 ) (361 ) (152 ) Fair value of plan assets — end of year 4,630 8,649 49,703 43,601 — — Reconciliation: Funded status (1,584 ) (2,063 ) (15,601 ) (15,776 ) (2,157 ) (2,285 ) Accrued pension cost $ (1,584 ) $ (2,063 ) $ (15,601 ) $ (15,776 ) $ (2,157 ) $ (2,285 ) Assumptions: Discount rate 3.00 % 4.00 % 3.25 % 4.25 % 3.00 % 4.00 % Expected return on plan assets 6.00 % 6.00 % 6.50 % 6.50 % — % — % Chesapeake FPU Chesapeake For the Years Ended December 31, 2019 (1) 2018 2017 2019 2018 2017 2019 2018 2017 (in thousands) Components of net periodic pension cost: Interest cost $ 375 $ 384 $ 402 $ 2,452 $ 2,339 $ 2,482 $ 74 $ 83 $ 89 Expected return on assets (487 ) (542 ) (495 ) (2,770 ) (3,091 ) (2,779 ) — — — Amortization of actuarial loss 391 343 399 505 404 513 85 101 87 Settlement expense 1,982 — — — — — 58 — — Net periodic pension cost 2,261 185 306 187 (348 ) 216 217 184 176 Amortization of pre-merger regulatory asset — — — 543 761 761 — — — Total periodic cost $ 2,261 $ 185 $ 306 $ 730 $ 413 $ 977 $ 217 $ 184 $ 176 Assumptions: Discount rate 3.00 % 3.50 % 3.75 % 4.25 % 3.75 % 4.00 % 4.00 % 3.50 % 3.75 % Expected return on plan assets 6.00 % 6.00 % 6.00 % 6.50 % 6.50 % 6.50 % — % — % — % (1) As a result of annuity purchases and lump sum payments associated with the de-risking of the Chesapeake Pension Plan, the discount rate for Chesapeake Pension Plan was remeasured which triggered settlement accounting expense in the fourth quarter of 2019. We recorded $0.7 million of the settlement expense in our consolidated statement of income which reflected a portion of the pension settlement expense that was deemed not recoverable through the regulatory process . Included in the net periodic costs for the FPU Pension Plan is amortization of the FPU pension regulatory asset, which represents the portion attributable to FPU's regulated operations for the changes in funded status that occurred, but were not recognized as part of net periodic cost, prior to the merger with Chesapeake Utilities in October 2009. This was previously deferred as a regulatory asset to be recovered through rates pursuant to an order by the Florida PSC. At December 31, 2019 , this regulatory asset was fully amortized. Excluding the service cost component, the other components of the net periodic costs have been recorded or reclassified to other expense, net of tax, in the consolidated statements of income. Our funding policy provides that payments to the trustee of each qualified plan shall be equal to at least the minimum funding requirements of the Employee Retirement Income Security Act of 1974. The changes in investment types for the Chesapeake Pension Plan at December 31, 2019 , compared to same period in 2018, are associated with the de-risking strategy executed during the fourth quarter of 2019. The following schedule summarizes the assets of the Chesapeake Pension Plan and the FPU Pension Plan, by investment type, at December 31, 2019 , 2018 and 2017 : Chesapeake Pension Plan FPU Pension Plan At December 31, 2019 2018 2017 2019 2018 2017 Asset Category Equity securities — % 49 % 53 % 53 % 50 % 55 % Debt securities 92 % 41 % 38 % 37 % 41 % 37 % Other 8 % 10 % 9 % 10 % 9 % 8 % Total 100 % 100 % 100 % 100 % 100 % 100 % The investment policy of both the Chesapeake Utilities and FPU Pension Plans is designed to provide the capital assets necessary to meet the financial obligations of the plans. The investment goals and objectives are to achieve investment returns that, together with contributions, will provide funds adequate to pay promised benefits to present and future beneficiaries of the plans, earn a competitive return to increasingly fund a large portion of the plans’ retirement liabilities, minimize pension expense and cumulative contributions resulting from liability measurement and asset performance, and maintain the appropriate mix of investments to reduce the risk of large losses over the expected remaining life of each plan. The following allocation range of asset classes is intended to produce a rate of return sufficient to meet the plans’ goals and objectives (this allocation range applied to Chesapeake Pension Plan prior to the de-risking strategy executed during the fourth quarter of 2019): Asset Allocation Strategy Asset Class Minimum Allocation Percentage Maximum Allocation Percentage Domestic Equities (Large Cap, Mid Cap and Small Cap) 14 % 32 % Foreign Equities (Developed and Emerging Markets) 13 % 25 % Fixed Income (Inflation Bond and Taxable Fixed) 26 % 40 % Alternative Strategies (Long/Short Equity and Hedge Fund of Funds) 6 % 14 % Diversifying Assets (High Yield Fixed Income, Commodities, and Real Estate) 7 % 19 % Cash 0 % 5 % Due to periodic contributions and different asset classes producing varying returns, the actual asset values may temporarily move outside of the intended ranges. The investments are monitored on a quarterly basis, at a minimum, for asset allocation and performance. At December 31, 2019 and 2018 , the assets of the Chesapeake Pension Plan and the FPU Pension Plan were comprised of the following investments: Fair Value Measurement Hierarchy At December 31, 2019 At December 31, 2018 Asset Category Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total (in thousands) Mutual Funds - Equity securities U.S. Large Cap (1) $ 3,553 $ — $ — $ 3,553 $ 3,399 $ — $ — $ 3,399 U.S. Mid Cap (1) 1,604 — — 1,604 1,478 — — 1,478 U.S. Small Cap (1) 726 — — 726 670 — — 670 International (2) 9,855 — — 9,855 9,226 — — 9,226 Alternative Strategies (3) 4,739 — — 4,739 5,726 — — 5,726 20,477 — — 20,477 20,499 — — 20,499 Mutual Funds - Debt securities Fixed income (4) 19,220 — — 19,220 18,630 — — 18,630 High Yield (4) 2,476 — — 2,476 2,818 — — 2,818 21,696 — — 21,696 21,448 — — 21,448 Mutual Funds - Other Commodities (5) 1,708 — — 1,708 1,902 — — 1,902 Real Estate (6) 2,288 — — 2,288 2,216 — — 2,216 Guaranteed deposit (7) — — 1,147 1,147 — — 627 627 3,996 — 1,147 5,143 4,118 — 627 4,745 Total Pension Plan Assets in fair value hierarchy $ 46,169 $ — $ 1,147 47,316 $ 46,065 $ — $ 627 46,692 Investments measured at net asset value (8) 7,017 5,558 Total Pension Plan Assets $ 54,333 $ 52,250 (1) Includes funds that invest primarily in United States common stocks. (2) Includes funds that invest primarily in foreign equities and emerging markets equities. (3) Includes funds that actively invest in both equity and debt securities, funds that sell short securities and funds that provide long-term capital appreciation. The funds may invest in debt securities below investment grade. (4) Includes funds that invest in investment grade and fixed income securities. (5) Includes funds that invest primarily in commodity-linked derivative instruments and fixed income securities. (6) Includes funds that invest primarily in real estate. (7) Includes investment in a group annuity product issued by an insurance company. (8) Certain investments that were measured at net asset value per share have not been classified in the fair value hierarchy. These amounts are presented to reconcile to total pension plan assets. At December 31, 2019 and 2018 , all of the investments were classified under the same fair value measurement hierarchy (Level 1 through Level 3) described under Note 9 , Fair Value of Financial Instruments . The Level 3 investments were recorded at fair value based on the contract value of annuity products underlying guaranteed deposit accounts, which was calculated using discounted cash flow models. The contract value of these products represented deposits made to the contract, plus earnings at guaranteed crediting rates, less withdrawals and fees. The following table sets forth the summary of the changes in the fair value of Level 3 investments for the years ended December 31, 2019 and 2018 : For the Year Ended December 31, 2019 2018 (in thousands) Balance, beginning of year $ 627 $ 436 Purchases 2,274 1,674 Transfers in 3,090 2,375 Disbursements (4,907 ) (3,872 ) Investment income 63 14 Balance, end of year $ 1,147 $ 627 Other Postretirement Benefits Plans We sponsor two defined benefit postretirement health plans: the Chesapeake Postretirement Plan and the FPU Medical Plan. The following table sets forth the funded status at December 31, 2019 and 2018 : Chesapeake FPU At December 31, 2019 2018 2019 2018 (in thousands) Change in benefit obligation: Benefit obligation — beginning of year $ 1,002 $ 1,128 $ 1,187 $ 1,287 Interest cost 39 38 48 47 Plan participants contributions 149 136 38 41 Actuarial loss (gain) 73 (131 ) 47 (89 ) Benefits paid (163 ) (169 ) (96 ) (99 ) Benefit obligation — end of year 1,100 1,002 1,224 1,187 Change in plan assets: Fair value of plan assets — beginning of year — — — — Employer contributions (1) 14 33 58 58 Plan participants contributions 149 136 38 41 Benefits paid (163 ) (169 ) (96 ) (99 ) Fair value of plan assets — end of year — — — — Reconciliation: Funded status (1,100 ) (1,002 ) (1,224 ) (1,187 ) Accrued postretirement cost $ (1,100 ) $ (1,002 ) $ (1,224 ) $ (1,187 ) Assumptions: Discount rate 3.00 % 4.00 % 3.25 % 4.25 % (1) The Chesapeake Postretirement Plan does not receive a Medicare Part-D subsidy. The FPU Medical Plan did not receive a significant subsidy for the post-merger period. Net periodic postretirement benefit costs for 2019 , 2018 , and 2017 include the following components: Chesapeake FPU For the Years Ended December 31, 2019 2018 2017 2019 2018 2017 (in thousands) Components of net periodic postretirement cost: Interest cost $ 39 $ 38 $ 41 $ 48 $ 47 $ 50 Amortization of actuarial loss 46 58 53 — — — Amortization of prior service cost (credit) (77 ) (77 ) (77 ) — — — Net periodic cost 8 19 17 48 47 50 Amortization of pre-merger regulatory asset — — — 8 8 8 Total periodic cost $ 8 $ 19 $ 17 $ 56 $ 55 $ 58 Assumptions Discount rate 4.00 % 3.50 % 3.75 % 4.25 % 3.75 % 4.00 % The following table presents the amounts not yet reflected in net periodic benefit cost and included in accumulated other comprehensive loss or as a regulatory asset as of December 31, 2019 : (in thousands) Chesapeake Pension Plan FPU Pension Plan Chesapeake SERP Chesapeake Postretirement Plan FPU Medical Plan Total Prior service cost (credit) $ — $ — $ — $ (447 ) $ — $ (447 ) Net loss (gain) 2,241 19,339 575 604 (32 ) 22,727 Total $ 2,241 $ 19,339 $ 575 $ 157 $ (32 ) $ 22,280 Accumulated other comprehensive loss (gain) pre-tax (1) $ 2,241 $ 3,674 $ 575 $ 157 $ (6 ) $ 6,641 Post-merger regulatory asset — 15,665 — — (26 ) 15,639 Subtotal 2,241 19,339 575 157 (32 ) 22,280 Pre-merger regulatory asset — — — — 6 6 Total unrecognized cost $ 2,241 $ 19,339 $ 575 $ 157 $ (26 ) $ 22,286 (1) The total amount of accumulated other comprehensive loss recorded on our consolidated balance sheet as of December 31, 2019 is net of income tax benefits of $1.7 million . Pursuant to a Florida PSC order, FPU continues to record as a regulatory asset a portion of the unrecognized pension and postretirement benefit costs after the merger with Chesapeake Utilities related to its regulated operations, which is included in the above table as a post-merger regulatory asset. FPU continues to maintain and amortize a portion of the unrecognized postretirement benefit costs prior to the merger with Chesapeake Utilities related to its regulated operations, which is shown as a pre-merger regulatory asset. The portion of the regulatory asset related to the FPU Pension was fully amortized at December 31, 2019. Assumptions The assumptions used for the discount rate to calculate the benefit obligations were based on the interest rates of high-quality bonds in 2019 , considering the expected lives of each of the plans. In determining the average expected return on plan assets for each applicable plan, various factors, such as historical long-term return experience, investment policy and current and expected allocation, were considered. Since Chesapeake Utilities' plans and FPU’s plans have different expected plan lives, particularly in light of the lump-sum-payment option provided in the Chesapeake Pension Plan and the de-risking strategy implemented in the fourth quarter of 2019 for Chesapeake's Plan, different assumptions regarding discount rate and expected return on plan assets were selected for Chesapeake Utilities' and FPU’s plans. Since both pension plans are frozen with respect to additional years of service and compensation, the rate of assumed compensation increases is not applicable. The health care inflation rate for 2019 used to calculate the benefit obligation is 5.0 percent for medical and 6.0 percent for prescription drugs for the Chesapeake Postretirement Plan; and 5.0 percent for both medical and prescription drugs for the FPU Medical Plan. Estimated Future Benefit Payments In 2020 , we expect to contribute $0.3 million and $3.2 million to the Chesapeake Pension Plan and FPU Pension Plan, respectively, and $0.2 million to the Chesapeake SERP. We also expect to contribute $0.1 million to both the Chesapeake Postretirement Plan and FPU Medical Plan, in 2020 . The schedule below shows the estimated future benefit payments for each of the plans previously described: Chesapeake Pension Plan (1) FPU Pension Plan (1) Chesapeake SERP (2) Chesapeake Postretirement Plan (2) FPU Medical Plan (2) (in thousands) 2020 $ 115 $ 3,281 $ 151 $ 90 $ 86 2021 $ 368 $ 3,348 $ 150 $ 87 $ 90 2022 $ 106 $ 3,424 $ 148 $ 85 $ 91 2023 $ 927 $ 3,498 $ 146 $ 67 $ 79 2024 $ 111 $ 3,549 $ 144 $ 64 $ 80 Years 2025 through 2029 $ 2,300 $ 18,429 $ 748 $ 264 $ 389 (1) The pension plan is funded; therefore, benefit payments are expected to be paid out of the plan assets. (2) Benefit payments are expected to be paid out of our general funds. Retirement Savings Plan For the years ended December 31, 2019 , 2018 and 2017 , we sponsored a 401(k) Retirement Savings Plan. This plan is offered to all eligible employees who have completed three months of service. We match 100 percent of eligible participants’ pre-tax contributions to the Retirement Savings Plan up to a maximum of six percent of eligible compensation. The employer matching contribution is made in cash and is invested based on a participant’s investment directions. In addition, we may make a discretionary supplemental contribution to participants in the plan, without regard to whether or not they make pre-tax contributions. Any supplemental employer contribution is generally made in our common stock. With respect to the employer match and supplemental employer contribution, employees are 100 percent vested after two years of service or upon reaching 55 years of age while still employed by us. New employees who do not make an election to contribute and do not opt out of the Retirement Savings Plan will be automatically enrolled at a deferral rate of three percent , and the automatic deferral rate will increase by one percent per year up to a maximum of ten percent . All contributions and matched funds can be invested among the mutual funds available for investment. Employer contributions to our Retirement Savings Plan totaled $5.7 million , $5.5 million , and $5.0 million for the years ended December 31, 2019 , 2018 and 2017 , respectively. As of December 31, 2019 , there were 831,183 shares of our common stock reserved to fund future contributions to the Retirement Savings Plan. Non-Qualified Deferred Compensation Plan Members of our Board of Directors, and officers designated by the Compensation Committee, are eligible to participate in the Non-Qualified Deferred Compensation Plan. Directors can elect to defer any portion of their cash or stock compensation and officers can defer up to 80 percent of their base compensation, cash bonuses or any amount of their stock bonuses (net of required withholdings). Officers may receive a matching contribution on their cash compensation deferrals up to six percent of their compensation, provided it does not duplicate a match they receive in the Retirement Savings Plan. Stock bonuses are not eligible for matching contributions. Participants are able to elect the payment of deferred compensation to begin on a specified future date or upon separation from service. Additionally, participants can elect to receive payments upon the earlier or later of a fixed date or separation from service. The payments can be made in one lump sum or annual installments for up to 15 years . All obligations arising under the Non-Qualified Deferred Compensation Plan are payable from our general assets, although we have established a Rabbi Trust to informally fund the plan. Deferrals of cash compensation may be invested by the participants in various mutual funds (the same options that are available in the Retirement Savings Plan). The participants are credited with gains or losses on those investments. Deferred stock compensation may not be diversified. The participants are credited with dividends on our common stock in the same amount that is received by all other stockholders. Such dividends are reinvested into our common stock. Assets held in the Rabbi Trust, recorded as Investments on the consolidated balance sheet, had a fair value of $9.2 million and $6.7 million at December 31, 2019 and 2018 , respectively. (See Note 10, Investments , for further details). The assets of the Rabbi Trust are at all times subject to the claims of our general creditors. Deferrals of officer base compensation and cash bonuses and directors’ cash retainers are paid in cash. All deferrals of executive performance shares, which represent deferred stock units, and directors’ stock retainers are paid in shares of our common stock, except that cash is paid in lieu of fractional shares. The value of our stock held in the Rabbi Trust is classified within the stockholders’ equity section of the consolidated balance sheets and has been accounted for in a manner similar to treasury stock. The amounts recorded under the Non-Qualified Deferred Compensation Plan totaled $4.5 million and $3.9 million at December 31, 2019 and 2018

Share-Based Compensation Plans

Share-Based Compensation Plans	12 Months Ended
	Dec. 31, 2019
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Share-Based Compensation Plans	S HARE -B ASED C OMPENSATION P LANS Our non-employee directors and key employees have been 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. We have 449,868 shares of common stock reserved for issuance under the SICP. The table below presents the amounts included in net income related to share-based compensation expense for the awards granted under the SICP for the years ended December 31, 2019 , 2018 and 2017 : For the Year Ended December 31, 2019 2018 2017 (in thousands) Awards to non-employee directors $ 620 $ 539 $ 540 Awards to key employees 3,659 2,871 1,950 Total compensation expense 4,279 3,410 2,490 Less: tax benefit (1,117 ) (934 ) (1,003 ) Share-based compensation amounts included in net income $ 3,162 $ 2,476 $ 1,487 Stock Options There were no stock options outstanding or issued during the years 2017 through 2019 . Non-employee Directors Shares granted to non-employee directors are issued in advance of these directors’ service periods and are fully vested as of the date of the grant. We record a prepaid expense equal to the fair value of the shares issued and amortize the expense equally over a service period of one year . In May 2018 , each of our non-employee directors received an annual retainer of 792 shares of common stock under the SICP for board service through the 2019 Annual Meeting of Stockholders; accordingly, 7,128 shares, with a weighted average fair value of $75.70 per share, were issued and vested in 2018 . In May 2019 , each of our non-employee directors received an annual retainer of 751 shares of common stock under the SICP for service as a director through the 2020 Annual Meeting of Stockholders; accordingly, 6,759 shares, with a weighted average fair value of $93.14 per share, were issued and vested in 2019. In January 2020, a newly appointed member of the Board of Directors received a pro-rated retainer of 254 shares of common stock under the SICP to serve as a non-employee director through the 2020 Annual Meeting of Stockholders. The shares awarded to the non-employee director immediately vested upon issuance in January 2020, had a weighted average fair value of $95.83 per share, and the expense will be recognized over the remaining service period ending on the 2020 Annual Meeting of Stockholders. At December 31, 2019 , there was $0.2 million of unrecognized compensation expense related to shares granted to non-employee directors. This expense will be recognized over the remaining service period ending on the 2020 Annual Meeting of Stockholders. Our former President and Chief Executive Officer, Michael P. McMasters, retired as an executive officer on December 31, 2018 but continued as a member of the Board of Directors until the 2019 Annual Meeting of Stockholders. Mr. McMasters received a pro-rated grant of 276 shares of common stock under the SICP for service as a non-employee director from January 1, 2019 through May 8, 2019. The shares awarded to Mr. McMasters vested immediately upon issuance in January 2019, had a weighted average fair value of $81.30 per share, and were fully expensed as of the 2019 Annual Meeting of Stockholders. Key Employees Our Compensation Committee is authorized to grant our key employees the right to receive awards of shares of our common stock, contingent upon the achievement of established performance goals and subject to SEC transfer restrictions once awarded. We currently have several outstanding multi-year performance plans, which are based upon the successful achievement of long-term goals, growth and financial results and comprise both market-based and performance-based conditions or targets. The fair value per share, tied to a performance-based condition or target, is equal to the market price per share on the grant date. For the market-based conditions, we used the Black-Scholes pricing model to estimate the fair value of each share granted. The table below presents the summary of the stock activity for awards to key employees: Number of Shares Weighted Average Fair Value Outstanding — December 31, 2017 132,642 $ 59.31 Granted 49,494 67.76 Vested (29,786 ) 47.39 Vested - Accelerated pursuant to separation agreement (16,676 ) 75.78 Expired (3,933 ) 49.66 Outstanding — December 31, 2018 131,741 67.24 Granted (1) 88,048 92.74 Vested (25,831 ) 67.08 Expired (15,086 ) 69.28 Forfeited (2) (21,055 ) 71.67 Outstanding — December 31, 2019 157,817 $ 80.28 (1) Includes 43,032 shares that were granted to certain key employees in December 2019 associated with their promotion. (2) In conjunction with the retirement of two key employees during 2019, these shares were forfeited for the remainder of the service periods associated with awards granted during their employment with the Company. The intrinsic value of these awards was $15.1 million , $10.7 million and $10.4 million in 2019 , 2018 and 2017 , respectively. At December 31, 2019 , there was $4.3 million of unrecognized compensation cost related to these awards, which is expected to be recognized through 2021 . In June 2018, we entered into a separation agreement and release (the "Separation Agreement") with a former executive officer. Pursuant to the Separation Agreement, three awards, representing a total of 14,107 shares of common stock previously granted to the executive officer under the SICP, immediately vested at the time of separation; 2,569 shares were forfeited, and we recognized $1.1 million as share-based compensation expense. In 2019 , 2018 and 2017 , we withheld shares with a value at least equivalent to the employees’ minimum statutory obligation for the applicable income and other employment taxes, and remitted the cash to the appropriate taxing authorities with the executives electing to receive the net shares. The below table presents the number of shares withheld, amounts remitted to taxing authorities and the tax benefits associated with these obligations: For the Year Ended December 31, 2019 2018 2017 (amounts except shares, in thousands) Shares withheld to satisfy tax obligations 7,635 16,918 10,269 Amounts remitted to tax authorities to satisfy obligations $ 692 $ 1,210 $ 692 Tax benefit associated with settlement of share based payments $ — $ — $ 349

Rates and Other Regulatory Acti

Rates and Other Regulatory Activities	12 Months Ended
	Dec. 31, 2019
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Rates and Other Regulatory Activities	R ATES AND O THER R EGULATORY A CTIVITIES 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, our intrastate pipeline subsidiary, is subject to regulation (excluding cost of service) by the Florida PSC. Delaware Effect of the TCJA on Customers: In January 2019, the Delaware PSC approved the as-filed Delaware Division Delivery Service Rates reflecting the impact of the TCJA. The new rates went into effect in March 2019. The refunds, which were retroactive to February 2018, were completed prior to the mandated deadline of June 2019. The order also provided for a line item billing credit that went into effect in April 2019, for the return of the excess accumulated deferred income taxes ("ADIT"). CGS: In August 2019, we filed with the Delaware PSC an application seeking an order that will establish the regulatory accounting treatment and valuation methodology for the acquisition of propane CGS owned by our affiliate, Sharp, and the conversion of the CGS to natural gas service. We propose to acquire each CGS one at a time and to pay replacement cost for each CGS system. In addition, we are requesting authorization to pay for and capitalize the CGS residents’ behind-the-meter conversion costs. Our existing natural gas customers will be protected against subsidizing the acquisitions and conversions of the CGS systems because we will complete only those systems that meet our economic test. In September 2019, the Delaware PSC issued an order to open a docket for the purpose of reviewing our application and to conduct evidentiary hearings on the matter. We are currently responding to discovery requests and an evidentiary hearing is scheduled for the second quarter of 2020. Maryland Approval of the Elkton Gas Company Acquisition: In December 2019, we entered into an agreement with SJI to acquire its subsidiary, Elkton Gas Company, which provides natural gas distribution service to approximately 7,000 residential and commercial customers within a franchised area of Cecil County, Maryland. Upon completion of the transaction, Elkton Gas Company will become our wholly-owned subsidiary. The acquisition, which is expected to close in the second half of 2020, is subject to approval by the Maryland PSC. Elkton Gas Company's territory is contiguous to our franchised service territory in Cecil County, Maryland and it will continue to operate out of its existing office with the same local personnel. Florida Electric Limited Proceeding-Storm Recovery (Pre-Hurricane Michael): In February 2018, FPU filed a petition with the Florida PSC, requesting recovery of incremental storm restoration costs related to several hurricanes and tropical storms, along with the replenishment of the storm reserve to its pre-storm level of $1.5 million . As a result of these hurricanes and tropical storms, FPU’s storm reserve was depleted and, at the time of filing the petition, had a deficit of $0.8 million . This matter went to hearing in December 2018 and was subsequently approved at the March 2019 Agenda with the Final Order issued on March 25, 2019. FPU received approval to begin a surcharge on customer bills for two years beginning in April 2019, to recover storm-related costs and replenish the storm reserve. Hurricane Michael: In October 2018, Hurricane Michael passed through FPU's electric distribution operation's service territory in Northwest Florida. The hurricane caused widespread and severe damage to FPU's infrastructure resulting in the loss of electric service to 100 percent of its customers in the Northwest Florida service territory. FPU, after exerting extraordinary hurricane restoration efforts, restored service to those customers who were able to accept it. FPU expended more than $65.0 million to restore service, which was recorded as new plant and equipment, charged against FPU’s accumulated depreciation or charged against FPU’s storm reserve. Additionally, amounts currently being reviewed by the Florida PSC for regulatory asset treatment have been recorded as receivables and other deferred charges. In December 2018 and January 2019, we executed two 13 -month unsecured term loans as temporary financing for the Hurricane Michael-related expenditures, each in the amount of $30.0 million . The interest cost associated with these loans is the one-month LIBOR rate plus 75 basis points. In December 2019, we utilized the proceeds from the issuance of uncollateralized senior notes to repay the term notes issued in December 2018. In August 2019, FPU filed a limited proceeding requesting recovery of storm-related costs associated with Hurricane Michael (capital and expenses) through a change in base rates. FPU also requested treatment and recovery of certain storm-related costs as regulatory assets for items currently not allowed to be recovered through the storm reserve as well as the recovery of capital replaced as a result of the storm. Recovery of these costs includes a component of an overall return on capital additions and regulatory assets. In the fourth quarter of 2019, FPU along with the Office of Public Counsel in Florida, filed a joint motion with the Florida PSC to approve an interim rate increase, subject to refund, pending the final ruling on the recovery of the restoration costs incurred. The petition was approved by the Florida PSC in November 2019 and temporary rate increases were implemented effective January 2020. FPU continues to work with the Florida PSC and expects to reach a final ruling in the second half of 2020. Effect of the TCJA on Customers: In February 2018, the Florida PSC opened dockets to consider the impacts associated with the TCJA. In May 2018, FPU’s natural gas divisions filed petitions and supporting testimony regarding the disposition of the related impacts of the TCJA. Hearings on this matter took place in November 2018, and the staff's recommendation was approved by the Florida PSC at the February 2019 Agenda and final orders were issued on February 25, 2019. Staff’s recommendations are summarized in the table at the end of this section. Electric Depreciation Study: In September 2019, FPU filed a petition, with the Florida PSC, for approval of its consolidated electric depreciation rates. The new rates will be effective January 1, 2020. The petition has not been scheduled for approval by the Florida PSC. Natural Gas Depreciation Study: In March 2019, FPU filed a petition, with the Florida PSC, for approval of its consolidated natural gas depreciation rates. The petition was approved by the Florida PSC at Agenda on October 3, 2019. The new rates were effective retroactive to January 1, 2019, and are expected to decrease depreciation expense by approximately $0.9 million annually. Auburndale Project: In June 2019, Peninsula Pipeline filed with the Florida PSC for approval of its Transportation Service Agreement with the Florida Division of Chesapeake Utilities. Peninsula Pipeline will purchase an existing pipeline owned by the Florida Division of Chesapeake Utilities and Calpine and construct pipeline facilities in Polk County, Florida. Peninsula Pipeline will provide transportation service to the Florida Division of Chesapeake Utilities increasing both delivery capacity and downstream pressure as well as introducing a secondary source of natural gas for the Florida Division of Chesapeake Utilities' distribution system. The petition was approved by the Florida PSC at the August 6, 2019 Agenda. The project was placed in service in the third quarter of 2019. Palm Beach Expansion Project: In June 2019, Peninsula Pipeline filed with the Florida PSC for approval of its Transportation Service Agreement with FPU. Peninsula Pipeline will construct 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, system pressure as well as introducing diversity in fuel source for natural gas to serve the increased demand in these areas. The petition was approved by the Florida PSC at the August 6, 2019 Agenda. Interim services began in the fourth quarter of 2019. Callahan Pipeline Project, Nassau County: In July 2019, Peninsula Pipeline filed a petition for approval of the firm transportation service agreement with FPU and the restructuring of the business and operational agreements between Peoples Gas, FPU and Seacoast Gas Transmission. Peninsula Pipeline will construct and jointly own 26 miles of 16 inch steel pipeline with Seacoast Gas Transmission and interconnect to the Cypress Pipeline interstate system in western Nassau County. The Callahan pipeline will terminate into the existing Peninsula Pipeline-Peoples Gas jointly owned pipeline, which serves Amelia Island and the Peoples Gas distribution system. Callahan pipeline will enhance FPU’s ability to expand service into Nassau County and will enable Peoples Gas to enhance its system pressure and reliability of its service in Duval County. This petition was approved by the Florida PSC at the December 10, 2019 Agenda. The project is expected to be placed in-service during the third quarter of 2020. 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, which was applied for in September 2018 by Eastern Shore, approved the construction and operation of new facilities that will provide an additional 14,300 Dts/d of firm service to four customers. Facilities to be constructed include 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. Eastern Shore anticipates that this project will be fully in-service by the beginning of the fourth quarter of 2021. Renewable Natural Gas Tariff: In October 2019, Eastern Shore filed an application with the FERC to include renewable natural gas (biogas) utilization and standards in its tariff. Eastern Shore had proposed changes to its gas quality specifications that would enable it to accommodate renewable natural gas at various receipt points on its system. Changes to the gas quality specifications would ensure interchangeability of renewable natural gas with the natural gas currently delivered to Eastern Shore. The tariffs became effective November 2019 after the end of 30 days of no opposing comments. Summary TCJA Table Regulatory Liabilities related to ADIT Operation and Regulatory Jurisdiction Amount (in thousands) Status Status of Customer Rate impact related to lower federal corporate income tax rate Eastern Shore (FERC) $34,190 Will be addressed in Eastern Shore's next rate case filing. Implemented one-time bill credit (totaling $0.9 million) in April 2018. Customer rates were adjusted in April 2018. Delaware Division (Delaware PSC) $12,847 PSC approved amortization of ADIT in January 2019. Implemented one-time bill credit (totaling $1.5 million) in April 2019. Customer rates were adjusted in March 2019. Maryland Division (Maryland PSC) $4,087 PSC approved amortization of ADIT in May 2018. Implemented one-time bill credit (totaling $0.4 million) in July 2018. Customer rates were adjusted in May 2018. Sandpiper Energy (Maryland PSC) $3,765 PSC approved amortization of ADIT in May 2018. Implemented one-time bill credit (totaling $0.6 million) in July 2018. Customer rates were adjusted in May 2018. Chesapeake Florida Gas Division/Central Florida Gas (Florida PSC) $8,304 PSC issued order authorizing amortization and retention of net ADIT liability by the Company in February 2019. Florida PSC's final order was issued in February 2019. Excluding GRIP, tax savings arising from the TCJA rate reduction will be retained by the Company. FPU Natural Gas (excludes Fort Meade and Indiantown) (Florida PSC) $19,218 Same treatment on a net basis as Chesapeake Florida Gas Division (above). Same treatment on a net basis as Chesapeake Florida Gas Division (above). FPU Fort Meade and Indiantown Divisions $294 Same treatment on a net basis as Chesapeake Florida Gas Division (above). Tax rate reduction: The impact was immaterial for the divisions. FPU Electric (Florida PSC) $5,769 In January 2019, PSC issued order approving amortization of ADIT through purchased power cost recovery, storm reserve and rates. TCJA benefit will flow back to its customers through a combination of reductions to the fuel cost recovery rate, base rates, as well as application to the storm reserve over the next several years. Regulatory Assets and Liabilities At December 31, 2019 and 2018 , our regulated utility operations had recorded the following regulatory assets and liabilities included in our consolidated balance sheets. These assets and liabilities will be recognized as revenues and expenses in future periods as they are reflected in customers’ rates. As of December 31, 2019 2018 (in thousands) Regulatory Assets Under-recovered purchased fuel and conservation cost recovery (1) $ 5,144 $ 4,631 Under-recovered GRIP revenue (2) — 165 Deferred postretirement benefits (3) 16,311 15,517 Deferred conversion and development costs (1) 20,881 16,727 Environmental regulatory assets and expenditures (4) 2,241 2,731 Acquisition adjustment (5) 30,329 33,255 Loss on reacquired debt (6) 869 942 Other 2,776 3,250 Total Regulatory Assets $ 78,551 $ 77,218 Regulatory Liabilities Self-insurance (7) $ 873 $ 947 Over-recovered purchased fuel and conservation cost recovery (1) 2,724 5,856 Over-recovered GRIP revenue (2) 2,668 1,563 Storm reserve (7) 1,437 677 Accrued asset removal cost (8) 36,767 42,401 Deferred income taxes due to rate change (9) 89,191 91,236 Other 75 242 Total Regulatory Liabilities $ 133,735 $ 142,922 (1) We are allowed to recover the asset or are required to pay the liability in rates. We do not earn an overall rate of return on these assets. (2) The Florida PSC allowed us to recover through a surcharge, capital and other program-related-costs, inclusive of an appropriate return on investment, associated with accelerating the replacement of qualifying distribution mains and services (defined as any material other than coated steel or plastic) in FPU’s natural gas distribution, Fort Meade division and Chesapeake Utilities’ Central Florida Gas division. We are allowed to recover the asset or are required to pay the liability in rates related to GRIP. (3) The Florida PSC allowed FPU to treat as a regulatory asset the portion of the unrecognized costs pursuant to ASC Topic 715 , Compensation - Retirement Benefits , related to its regulated operations. In 2019, we recorded as a regulatory asset the portion of pension settlement expense associated with the de-risking of the Chesapeake Pension Plan pursuant to an order from the FERC that allowed us to defer Eastern Shore's portion. See Note 17 , Employee Benefit Plans, for additional information. (4) All of our environmental expenditures incurred to date and our current estimate of future environmental expenditures have been approved by various PSCs for recovery. See Note 20 , Environmental Commitments and Contingencies , for additional information on our environmental contingencies. (5) We are allowed to include the premiums paid in various natural gas utility acquisitions in Florida in our rate bases and recover them over a specific time period pursuant to the Florida PSC approvals. We paid $34.2 million of the premium in 2009, including a gross up for income tax, because it is not tax deductible, and $0.7 million of the premium paid by FPU in 2010. (6) Gains and losses resulting from the reacquisition of long-term debt are amortized over future periods as adjustments to interest expense in accordance with established regulatory practice. (7) We have self-insurance and storm reserves in our Florida regulated energy operations that allow us to collect through rates amounts to be used against general claims, storm restoration costs and other losses as they are incurred. (8) See Note 1 , Summary of Significant Accounting Policies, for additional information on our asset removal cost policies. (9) We recorded a regulatory liability for our regulated businesses related to the revaluation of accumulated deferred tax assets/liabilities as a result of the TCJA. Based upon the regulatory proceedings, we will pass back the respective portion of the excess accumulated deferred taxes to rate payers. See Note 12, Income Taxes , for additional information.

Environmental Commitments and C

Environmental Commitments and Contingencies	12 Months Ended
	Dec. 31, 2019
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Environmental Commitments and Contingencies	E NVIRONMENTAL C OMMITMENTS AND C ONTINGENCIES 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 December 31, 2019 and 2018, we had approximately $8.0 million and $9.1 million , respectively, in environmental liabilities, related to FPU’s MGP sites in Key West, Pensacola, Sanford and West Palm Beach. FPU has approval to recover, from insurance and from customers through rates, up to $14.0 million of its environmental costs related to its MGP sites. As of December 31, 2019 and 2018, we have recovered approximately $11.9 million and $11.5 million , respectively, leaving approximately $2.1 million and $2.5 million , respectively, in regulatory assets for future recovery 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. The following is a summary of our remediation status and estimated costs to implement clean-up of our key MGP sites: MGP Site (Jurisdiction) Status Estimated Cost to Clean Up (Expect to Recover through Rates) West Palm Beach (Florida) Remedial actions approved by the Florida Department of Environmental Protection have been implemented on the east parcel of the site. We expect to implement similar remedial actions on the site's west parcel in 2020. Between $4.5 million to $15.4 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. Sanford (Florida) In March 2018, the United States Environmental Protection Agency ("EPA") approved a "site-wide ready for anticipated use" status, which is the final step before delisting a site. Construction has been completed and restrictive covenants are in place to ensure protection of human health. The only remaining activity is long-term groundwater monitoring. FPU's remaining remediation expenses, including attorneys' fees and costs, are anticipated to be immaterial. Winter Haven (Florida) Remediation is ongoing. Not expected to exceed $0.4 million. Seaford (Delaware) Conducted investigations of on-site and off-site impacts in the vicinity of the site, from 2014 through 2018, and submitted the findings to Delaware Department of Natural Resources and Environmental Control ("DNREC") in a March 2019 report. An interim action involving air-sparging/vapor extraction is being implemented, in accordance with the DNREC-approved Work Plan. Between $0.2 million and $0.5 million.

Other Commitments and Contingen

Other Commitments and Contingencies	12 Months Ended
	Dec. 31, 2019
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Other Commitments and Contingencies	O THER C OMMITMENTS AND C ONTINGENCIES Natural Gas, Electric and Propane Supply Our Delmarva Peninsula natural gas distribution operations had asset management agreements with PESCO to manage their natural gas transportation and storage capacity. The agreements were effective as of April 1, 2017, and each has a three -year term, expiring on March 31, 2020. As a result of the sale of PESCO's assets and contracts, effective October 1, 2019, these agreements are now managed by NJRES. See Note 4, Acquisitions and Divestitures for additional details regarding the sale of PESCO's assets and contracts. In May 2019, FPU natural gas distribution operations and Eight Flags entered into separate asset management agreements with Emera Energy Services, Inc. to manage their natural gas transportation capacity. Long-term agreements will commence on or about July 2020, and each has a 10 -year term. Short-term agreements were entered for a one year term beginning July 2019 through July 2020. 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 2 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 December 31, 2019 , 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. Eight Flags sells power generated from the CHP plant to FPU pursuant to a 20 -year power purchase agreement for distribution to our electric customers. Eight Flags also sells steam and heated water pursuant to a separate 20 -year contract, to Rayonier 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. The total purchase obligations for natural gas, electric and propane supplies are as follows: Year 2020 2021-2022 2023-2024 Beyond 2024 Total (in thousands) Purchase Obligations $ 60,735 $ 72,123 $ 60,049 $ 201,131 $ 394,038 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 December 31, 2019 was $37.0 million . The aggregate amount guaranteed at December 31, 2019 was approximately $24.7 million , of which $16.3 million is related to the operations of PESCO, with the guarantees expiring on various dates through October 2020 . The amounts related to PESCO will decrease as soon as those guarantees are transferred to the respective counterparties. See Note 4, Acquisitions and Divestitures , for additional details on the sale of assets and contracts for PESCO. Chesapeake Utilities also guarantees the payment of FPU’s first mortgage bonds. The maximum exposure under this guarantee is the outstanding principal plus accrued interest balances. The outstanding principal balances of FPU’s first mortgage bonds approximate their carrying values (see Note 13 , Long-Term Debt , for further details). As of December 31, 2019 , we have issued letters of credit totaling approximately $5.4 million related to the electric transmission services for FPU's electric division, the firm transportation service agreement between TETLP and our Delaware and Maryland divisions and our current and previous primary insurance carriers. These letters of credit have various expiration dates through August 22, 2020. There have been no draws on these letters of credit as of December 31, 2019 . We do not anticipate that the counterparties will draw upon these letters of credit, and we expect that they will be renewed to the extent necessary in the future. The outstanding letters of credit as of December 31, 2019 also included those issued to support the operations of our divested subsidiary, PESCO. As a result of the sale of assets and contracts for PESCO, letters of credit related to PESCO will be terminated early or expire without being renewed in 2020.

Quarterly Financial Data

Quarterly Financial Data	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Quarterly Financial Data (Unaudited)	Q UARTERLY F INANCIAL D ATA (U NAUDITED ) In our opinion, the quarterly financial information shown below includes all adjustments necessary for a fair presentation of the operations for such periods. Due to the seasonal nature of our business, there are substantial variations in operations reported on a quarterly basis. For the Quarters Ended March 31 June 30 September 30 December 31 (in thousands except per share amounts) 2019 (1) Operating Revenues $ 160,464 $ 94,541 $ 92,626 $ 131,973 Operating Income $ 44,123 $ 18,164 $ 14,358 $ 29,642 Net Income: Income from Continuing Operations $ 28,814 $ 8,913 $ 6,246 $ 17,169 Loss from Discontinued Operations, Net of Tax (149 ) (609 ) (624 ) (9 ) Gain on sale of Discontinued Operations, Net of Tax — — — 5,402 $ 28,665 $ 8,304 $ 5,622 $ 22,562 Basic Earnings Per Share of Common Stock: Earnings Per Share from Continuing Operations $ 1.76 $ 0.54 $ 0.38 $ 1.05 Earnings/(Loss) Per Share from Discontinued Operations (0.01 ) (0.03 ) (0.04 ) 0.33 $ 1.75 $ 0.51 $ 0.34 $ 1.38 Diluted Earnings Per Share of Common Stock: Earnings Per Share from Continuing Operations $ 1.75 $ 0.54 $ 0.38 $ 1.04 Earnings/(Loss) Per Share from Discontinued Operations (0.01 ) (0.04 ) (0.04 ) 0.33 $ 1.74 $ 0.50 $ 0.34 $ 1.37 2018 (1) Operating Revenues $ 168,831 $ 93,872 $ 93,400 $ 134,214 Operating Income $ 40,853 $ 12,238 $ 12,879 $ 28,873 Net Income: Income from Continuing Operations $ 27,271 $ 5,705 $ 6,090 $ 17,796 Income/(Loss) from Discontinued Operations (415 ) 680 (552 ) 5 $ 26,856 $ 6,385 $ 5,538 $ 17,801 Basic Earnings Per Share of Common Stock: Earnings Per Share from Continuing Operations $ 1.67 $ 0.35 $ 0.37 $ 1.09 Earnings/(Loss) Per Share from Discontinued Operations (0.03 ) 0.04 (0.03 ) — $ 1.64 $ 0.39 $ 0.34 $ 1.09 Diluted Earnings Per Share of Common Stock: Earnings Per Share from Continuing Operations $ 1.66 $ 0.35 $ 0.37 $ 1.09 Earnings/(Loss) Per Share from Discontinued Operations (0.02 ) 0.04 (0.04 ) — $ 1.64 $ 0.39 $ 0.33 $ 1.09 (1) The sum of the four quarters does not equal the total for the year due to rounding.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Use of Estimates	Use of Estimates The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates in measuring assets and liabilities and related revenues and expenses. These estimates involve judgments about various future economic factors that are difficult to predict and are beyond our control; therefore, actual results could differ from these estimates. As additional information becomes available, or actual amounts are determined, recorded estimates are revised. Consequently, operating results can be affected by revisions to prior accounting estimates.
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment are stated at original cost less accumulated depreciation or fair value, if impaired. Costs include direct labor, materials and third-party construction contractor costs, allowance for funds used during construction ("AFUDC"), and certain indirect costs related to equipment and employees engaged in construction. The costs of repairs and minor replacements are charged to expense as incurred, and the costs of major renewals and betterments are capitalized. Upon retirement or disposition of property within the regulated businesses, the gain or loss, net of salvage value, is charged to accumulated depreciation. Upon retirement or disposition of property owned by the unregulated businesses, the gain or loss, net of salvage value, is charged to income. A summary of property, plant and equipment for continuing operations by classification as of December 31, 2019 and 2018 is provided in the following table: As of December 31, (in thousands) 2019 2018 Property, plant and equipment Regulated Energy Natural gas distribution - Delmarva Peninsula and Florida $ 705,095 $ 657,630 Natural gas transmission - Delmarva Peninsula, Pennsylvania and Florida 608,727 537,654 Electric distribution 127,651 102,133 Unregulated Energy Propane operations – Mid-Atlantic and Florida 141,841 123,632 Natural gas transmission and supply – Ohio 73,658 70,225 Electricity and steam generation 35,436 35,239 Mobile CNG and pipeline solutions 14,014 7,240 Other unregulated energy 104 104 Other 40,006 34,584 Total property, plant and equipment 1,746,532 1,568,441 Less: Accumulated depreciation and amortization (336,876 ) (294,089 ) Plus: Construction work in progress 54,141 79,168 Net property, plant and equipment $ 1,463,797 $ 1,353,520 Contributions or Advances in Aid of Construction Customer contributions or advances in aid of construction reduce property, plant and equipment, unless the amounts are refundable to customers. Contributions or advances may be refundable to customers after a number of years based on the amount of revenues generated from the customers or the duration of the service provided to the customers. Refundable contributions or advances are recorded initially as liabilities. Non-refundable contributions reduce property, plant and equipment at the time of such determination. As of December 31, 2019 and 2018 , the non-refundable contributions totaled $2.1 million and $2.8 million , respectively. AFUDC Some of the additions to our regulated property, plant and equipment include AFUDC, which represents the estimated cost of funds, from both debt and equity sources, used to finance the construction of major projects. AFUDC is capitalized in the applicable rate base for ratemaking purposes when the completed projects are placed in service. During the years ended December 31, 2019 and 2018 , AFUDC totaled $0.7 million and $1.9 million , respectively, which was reflected as a reduction of interest charges. During the year ended December 31, 2017 , AFUDC was not material. Leases We have entered into lease arrangements for office space, land, equipment, pipeline facilities and warehouses. These leases enable us to conduct our business operations in the regions in which we operate. Our operating leases are included in operating lease right-of-use assets, other accrued liabilities, and operating lease - liabilities in our consolidated balance sheets. Right-of-use assets represent our right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. Operating lease right-of-use assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. Leases with an initial term of 12 months or less are not recorded on our balance sheet; we recognize lease expense for these leases on a straight-line basis over the lease term. Our leases do not provide an implicit lease rate, therefore, we utilize our incremental borrowing rate, as the basis to calculate the present value of future lease payments, at lease commencement. Our incremental borrowing rate represents the rate that we would have to pay to borrow funds on a collateralized basis over a similar term and in a similar economic environment. We have lease agreements with lease and non-lease components. At the adoption of ASC 842, we elected not to separate non-lease components from all classes of our existing leases. The non-lease components have been accounted for as part of the single lease component to which they are related. See Note 15, Leases for additional information. Jointly-owned Pipelines Property, plant and equipment for our Florida natural gas transmission operation also included $6.7 million of assets, at December 31, 2019 and 2018 , which consist of the 16 -mile pipeline from the Duval/Nassau County line to Amelia Island in Nassau County, Florida, jointly owned with Peoples Gas. The amount included in property, plant and equipment represents Peninsula Pipeline’s 45 -percent ownership of this pipeline. Peninsula Pipeline's share of direct expenses for the jointly-owned pipeline are included in operating expenses of our consolidated statements of income. Accumulated depreciation for this pipeline totaled $1.5 million and $1.4 million , at December 31, 2019 and 2018 , respectively. In May 2018, Peninsula Pipeline announced a plan to construct a jointly-owned 26 -mile intrastate transmission pipeline in Nassau County, Florida with Seacoast Gas Transmission. Peninsula Pipeline's ownership will be 50 percent. The pipeline is expected to be placed in-service during the third quarter of 2020. Asset Impairment Evaluations We periodically evaluate whether events or circumstances have occurred, which indicate that other long-lived assets may not be fully recoverable. The determination of whether an impairment has occurred is based on an estimate of undiscounted future cash flows attributable to the asset, compared to the carrying value of the asset. When such events or circumstances are present, we record an impairment loss equal to the excess of the asset's carrying value over its fair value, if any.
Depreciation and Accretion Included in Operations Expenses	Depreciation and Accretion Included in Operations Expenses We compute depreciation expense for our regulated operations by applying composite, annual rates, as approved by the respective regulatory bodies. The following table shows the average depreciation rates used for regulated operations during the years ended December 31, 2019 , 2018 and 2017 : 2019 2018 2017 Natural gas distribution – Delmarva Peninsula 2.5% 2.5% 2.5% Natural gas distribution – Florida 2.6% 2.9% 2.9% Natural gas transmission – Delmarva Peninsula 2.6% 2.7% 2.8% Natural gas transmission – Florida 2.4% 2.3% 3.5% Electric distribution 3.4% 3.4% 3.4% For our unregulated operations, we compute depreciation expense on a straight-line basis over the following estimated useful lives of the assets: Asset Description Useful Life Propane distribution mains 10-37 years Propane bulk plants and tanks 10-40 years Propane equipment, meters and meter installations 5-33 years Measuring and regulating station equipment 5-37 years Natural gas pipelines 45 years Natural gas right of ways Perpetual CHP plant 30 years Natural gas processing equipment 20-25 years Office furniture and equipment 3-10 years Transportation equipment 4-20 years Structures and improvements 5-45 years Other Various We report certain depreciation and accretion in operations expense, rather than as a depreciation and amortization expense, in the accompanying consolidated statements of income in accordance with industry practice and regulatory requirements. Depreciation and accretion included in operations expense consists of the accretion of the costs of removal for future retirements of utility assets, vehicle depreciation, computer software and hardware depreciation, and other minor amounts of depreciation expense. For the years ended December 31, 2019 , 2018 and 2017 , we reported $8.8 million , $8.5 million and $8.1 million , respectively, of depreciation and accretion in operations expenses.
Regulated Operations	Regulated Operations We account for our regulated operations in accordance with ASC Topic 980, Regulated Operations, which includes accounting principles for companies whose rates are determined by independent third-party regulators. When setting rates, regulators often make decisions, the economics of which require companies to defer costs or revenues in different periods than may be appropriate for unregulated enterprises. When this situation occurs, a regulated company defers the associated costs as regulatory assets on the balance sheet and records them as expense on the income statement as it collects revenues. Further, regulators can also impose liabilities upon a regulated company, for amounts previously collected from customers and for recovery of costs that are expected to be incurred in the future, as regulatory liabilities. If we were required to terminate the application of these regulatory provisions to our regulated operations, all such deferred amounts would be recognized in the statement of income at that time, which could have a material impact on our financial position, results of operations and cash flows. We monitor our regulatory and competitive environments to determine whether the recovery of our regulatory assets continues to be probable. If we determined that recovery of these assets is no longer probable, we would write off the assets against earnings. We believe that the provisions of ASC Topic 980, Regulated Operations, continue to apply to our regulated operations and that the recovery of our regulatory assets is probable.
Operating Revenues	Revenue Recognition Revenues for our natural gas and electric distribution operations are based on rates approved by the PSC in each state in which they operate. Customers’ base rates may not be changed without formal approval by these commissions. The PSCs, however, have authorized our regulated operations to negotiate rates, based on approved methodologies, with customers that have competitive alternatives. Eastern Shore’s revenues are based on rates approved by the FERC. The FERC has also authorized Eastern Shore to negotiate rates above or below the FERC-approved maximum rates, which customers can elect as an alternative to FERC-approved maximum rates. For regulated deliveries of natural gas and electricity, we read meters and bill customers on monthly cycles that do not coincide with the accounting periods used for financial reporting purposes. We accrue unbilled revenues for natural gas and electricity delivered, but not yet billed, at the end of an accounting period to the extent that they do not coincide. We estimate the amount of the unbilled revenue by jurisdiction and customer class. All of our regulated natural gas and electric distribution operations have fuel cost recovery mechanisms, except for two utilities that provide only unbundled delivery service (Chesapeake Utilities' Central Florida Gas division and FPU's Indiantown division). These mechanisms allow us to adjust billing rates, without further regulatory approvals, to reflect changes in the cost of purchased fuel. Differences between the cost of fuel purchased and delivered are deferred and accounted for as either unrecovered fuel cost or amounts payable to customers. Generally, these deferred amounts are recovered or refunded within one year. We charge flexible rates to our natural gas distribution industrial interruptible customers who can use alternative fuels. Interruptible service imposes no contractual obligation to deliver or receive natural gas on a firm service basis. Our unregulated propane delivery businesses record revenue in the period the products are delivered and/or services are rendered for their bulk delivery customers. For propane customers with meters whose billing cycles do not coincide with our accounting periods, we accrue unbilled revenue for product delivered but not yet billed and bill customers at the end of an accounting period, as we do in our regulated energy businesses. Our Ohio natural gas transmission/supply operation recognizes revenues based on actual volumes of natural gas shipped using contractual rates based upon index prices that are published monthly. Eight Flags records revenues based on the amount of electricity and steam generated and sold to its customers. Our mobile compressed natural gas operation recognizes revenue for CNG services at the end of each calendar month for services provided during the month based on agreed upon rates for labor, equipment utilized, costs incurred for natural gas compression, miles driven, mobilization and demobilization fees. We report revenue taxes, such as gross receipts taxes, franchise taxes, and sales taxes, on a net basis.
Cost of Sales	Cost of Sales Cost of sales includes the direct costs attributable to the products sold or services provided to our customers. These costs include primarily the variable commodity cost of natural gas, electricity and propane, costs of pipeline capacity needed to transport and store natural gas, transmission costs for electricity, costs to gather and process natural gas, costs to transport propane to/from our storage facilities or our mobile CNG equipment to customer locations, and steam and electricity generation costs. Depreciation expense is not included in cost of sales.
Operations and Maintenance Expenses	Operations and Maintenance Expenses Operations and maintenance expenses include operations and maintenance salaries and benefits, materials and supplies, usage of vehicles, tools and equipment, payments to contractors, utility plant maintenance, customer service, professional fees and other outside services, insurance expense, minor amounts of depreciation, accretion of removal costs for future retirements of utility assets and other administrative expenses.
Cash and Cash Equivalents	Cash and Cash Equivalents Our policy is to invest cash in excess of operating requirements in overnight income-producing accounts. Such amounts are stated at cost, which approximates fair value. Investments with an original maturity of three months or less when purchased are considered cash equivalents.
Accounts Receivable and Allowance for Doubtful Accounts	Accounts Receivable and Allowance for Doubtful Accounts Accounts receivable consist primarily of amounts due for sales of natural gas, electricity and propane and transportation and distribution services to customers. An allowance for doubtful accounts is recorded against amounts due based upon our collections experiences and an assessment of our customers’ inability or reluctance to pay. If circumstances change, our estimates of recoverable accounts receivable may also change. Circumstances which could affect such estimates include, but are not limited to, customer credit issues, natural gas, electricity and propane prices and general economic conditions. Accounts are written off when they are deemed to be uncollectible.
Inventories	Inventories We use the average cost method to value propane, materials and supplies, and other merchandise inventory. If market prices drop below cost, inventory balances that are subject to price risk are adjusted to their net realizable value. There was no lower-of-cost-or-net realizable value adjustment during 2019 , 2018 or 2017 .
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets Goodwill is not amortized but is tested for impairment at least annually, or more frequently if an event occurs or circumstances change that would more likely than not reduce the fair value of a reporting unit below its carrying value. We use a present value technique based on discounted cash flows to estimate the fair value of our reporting units. An impairment charge is recognized if the carrying value of a reporting unit’s goodwill exceeds its implied fair value. The testing of goodwill for 2019 , 2018 and 2017
Other Deferred Charges	Other Deferred Charges Other deferred charges include primarily issuance costs associated with short-term borrowings. These charges are amortized over the life of the related short-term debt borrowings.
Asset Retirement Obligation [Policy Text Block]	Asset Removal Cost
Pension and Other Postretirement Plans	Pension and Other Postretirement Plans Pension and other postretirement plan costs and liabilities are determined on an actuarial basis and are affected by numerous assumptions and estimates, including the fair value of plan assets, estimates of the expected returns on plan assets, assumed discount rates, the level of contributions made to the plans, and current demographic and actuarial mortality data. We review annually the estimates and assumptions underlying our pension and other postretirement plan costs and liabilities with the assistance of third-party actuarial firms. The assumed discount rates, expected returns on plan assets and the mortality assumption are the factors that generally have the most significant impact on our pension costs and liabilities. The assumed discount rates, health care cost trend rates and rates of retirement generally have the most significant impact on our postretirement plan costs and liabilities. The discount rates are utilized principally in calculating the actuarial present value of our pension and postretirement obligations and net pension and postretirement costs. When estimating our discount rates, we consider high-quality corporate bond rates, such as the Prudential curve index and the FTSE Pension Discount curve, formerly the Citigroup yield curve, changes in those rates from the prior year and other pertinent factors, including the expected life of each of our plans and their respective payment options. The expected long-term rates of return on assets are utilized in calculating the expected returns on the plan assets component of our annual pension plan costs. We estimate the expected returns on plan assets of each of our plans by evaluating expected bond returns, asset allocations, the effects of active plan management, the impact of periodic plan asset rebalancing and historical performance. We also consider the guidance from our investment advisors in making a final determination of our expected rates of return on assets. We estimate the health care cost trend rates used in determining our postretirement net expense based upon actual health care cost experience, the effects of recently enacted legislation and general economic conditions. Our assumed rate of retirement is estimated based upon our annual reviews of participant census information as of the measurement date.
Income Taxes and Investment Tax Credit Adjustments	Income Taxes, Investment Tax Credit Adjustments and Tax-Related Contingency Deferred tax assets and liabilities are recorded for the income tax effect of temporary differences between the financial statement basis and tax basis of assets and liabilities and are measured using the enacted income tax rates in effect in the years in which the differences are expected to reverse. Deferred tax assets are recorded net of any valuation allowance when it is more likely than not that such income tax benefits will be realized. Investment tax credits on utility property have been deferred and are allocated to income ratably over the lives of the subject property. We account for uncertainty in income taxes in our consolidated financial statements only if it is more likely than not that an uncertain tax position is sustainable based on technical merits. Recognizable tax positions are then measured to determine the amount of benefit recognized in the consolidated financial statements. We recognize penalties and interest related to unrecognized tax benefits as a component of other income. We account for contingencies associated with taxes other than income when the likelihood of a loss is both probable and estimable. In assessing the likelihood of a loss, we do not consider the existence of current inquiries, or the likelihood of future inquiries, by tax authorities as a factor. Our assessment is based solely on our application of the appropriate statutes and the likelihood of a loss, assuming the proper inquiries are made by tax authorities.
Financial Instruments	Financial Instruments Our propane operations enter into derivative transactions, such as swaps, put options and call options in order to mitigate the impact of wholesale price fluctuations on inventory valuation and future purchase commitments. These transactions may be designated as fair value hedges or cash flow hedges, if they meet all of the accounting requirements pursuant to ASC Topic 815, Derivatives and Hedging, and we elect to designate the instruments as hedges. If designated as a fair value hedge, the value of the hedging instrument, such as a swap, future, or put option, is recorded at fair value, with the effective portion of the gain or loss of the hedging instrument effectively reducing or increasing the value of the hedged item. If designated as a cash flow hedge, the value of the hedging instrument, such as a swap or call option, is recorded at fair value with the effective portion of the gain or loss of the hedging instrument being recorded in comprehensive income. The ineffective portion of the gain or loss of a hedge is recorded in earnings. If the instrument is not designated as a fair value or cash flow hedge, or it does not meet the accounting requirements of a hedge under ASC Topic 815, Derivatives and Hedging , it is recorded at fair value with all gains or losses being recorded directly in earnings. Our natural gas, electric and propane operations enter into agreements with suppliers to purchase natural gas, electricity, and propane for resale to our respective customers. Purchases under these contracts, as well as distribution and sales agreements with counterparties or customers, either do not meet the definition of a derivative, or qualify for “normal purchases and sales” treatment under ASC Topic 815 Derivatives and Hedging , and are accounted for on an accrual basis.
Recently Adopted Accounting Standards	Recently Adopted Accounting Standards Leases (ASC 842) - In February 2016, the FASB issued ASU 2016-02, Leases, which requires lessees to recognize leases on the balance sheet and disclose key information about leasing arrangements. The standard establishes a right of use model that requires a lessee to recognize a right of use asset and lease liability for all leases with a term greater than 12 months. The update also expands the required quantitative and qualitative disclosures surrounding leases. ASC 842 was subsequently amended by ASU No. 2018-01, Land Easement Practical Expedient for Transition to Topic 842 ; ASU No. 2018-10, Codification Improvements to Topic 842, Lease s; ASU No. 2018-11, Targeted Improvements ; and ASU No. 2019-01, Codification Improvements . We adopted ASU 2016-02 and the related amendments on January 1, 2019, and used the optional transition method for all existing leases. The optional transition method enabled us to adopt the new standard as of the beginning of the period of adoption and did not require restatement of prior period financial information. As a result, prior period financial information was not recast and continues to be reported under the accounting guidance effective during those periods. At adoption, we elected the following practical expedients: (1) the ‘package of practical expedients,’ pursuant to which we did not need to reassess our prior conclusions about lease identification, lease classification and initial direct costs, (2) the ‘use-of-hindsight’ practical expedient, which allowed us to use hindsight in assessing impairment of our existing land easements, (3) the creation of an accounting policy for short-term leases resulting in lease payments being recorded as an expense on a straight-line basis over the lease term, and (4) the aggregation, rather than separation, of the lease and non-lease components for all leases. See Note 15, Leases, for additional information with respect to the impact of the adoption of the lease accounting guidance and the disclosures required by ASU 2016-02 and the related amendments. Compensation - Stock Compensation (ASC 718) - In June 2018, the FASB issued ASU 2018-07, Improvements to Nonemployee Share-Based Payment Accounting
Schedule of Prospective Adoption of New Accounting Pronouncements [Table Text Block]	Recent Accounting Standards Yet to be Adopted Financial Instruments - Credit Losses (ASC 326) - In June 2016, the FASB issued ASU 2016-13, Measurement of Credit Losses on Financial Instruments , which changes how entities account for credit losses for most financial assets and certain other instruments, and subsequent guidance which served to clarify or amend the original standard. ASU 2016-13 and the related amendments require entities to estimate lifetime expected credit losses for trade receivables and to provide additional disclosure related to credit losses. ASU 2016-13 will be effective for our annual and interim financial statements beginning January 1, 2020 and is not expected to have a material impact on our financial position or results of operations. Intangibles - Goodwill (ASC 350) - In January 2017, the FASB issued ASU 2017-04, Simplifying the Test for Goodwill Impairment , which simplifies how an entity is required to test goodwill for impairment by eliminating Step 2 from the goodwill impairment test. ASU 2017-04 will be effective for our annual and interim financial statements beginning January 1, 2020, although early adoption is permitted. The amendments included in this ASU are to be applied prospectively, and are not expected to have a material impact on our financial position or results of operations. Fair Value Measurement (ASC 820) - In August 2018, the FASB issued ASU 2018-13, Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement , which removes, modifies and adds certain disclosure requirements on fair value measurements in ASC 820. ASU 2018-13 will be effective for our annual and interim financial statements beginning January 1, 2020, and since the changes only impact disclosures, will not have a material impact on our financial position or results of operations.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2019
Summary of Accounting poliicies [Abstract]
Property, Plant and Equipment [Table Text Block]	A summary of property, plant and equipment for continuing operations by classification as of December 31, 2019 and 2018 is provided in the following table: As of December 31, (in thousands) 2019 2018 Property, plant and equipment Regulated Energy Natural gas distribution - Delmarva Peninsula and Florida $ 705,095 $ 657,630 Natural gas transmission - Delmarva Peninsula, Pennsylvania and Florida 608,727 537,654 Electric distribution 127,651 102,133 Unregulated Energy Propane operations – Mid-Atlantic and Florida 141,841 123,632 Natural gas transmission and supply – Ohio 73,658 70,225 Electricity and steam generation 35,436 35,239 Mobile CNG and pipeline solutions 14,014 7,240 Other unregulated energy 104 104 Other 40,006 34,584 Total property, plant and equipment 1,746,532 1,568,441 Less: Accumulated depreciation and amortization (336,876 ) (294,089 ) Plus: Construction work in progress 54,141 79,168 Net property, plant and equipment $ 1,463,797 $ 1,353,520
Annual Depreciation Rates Table [Table Text Block]	Depreciation and Accretion Included in Operations Expenses We compute depreciation expense for our regulated operations by applying composite, annual rates, as approved by the respective regulatory bodies. The following table shows the average depreciation rates used for regulated operations during the years ended December 31, 2019 , 2018 and 2017 : 2019 2018 2017 Natural gas distribution – Delmarva Peninsula 2.5% 2.5% 2.5% Natural gas distribution – Florida 2.6% 2.9% 2.9% Natural gas transmission – Delmarva Peninsula 2.6% 2.7% 2.8% Natural gas transmission – Florida 2.4% 2.3% 3.5% Electric distribution 3.4% 3.4% 3.4%
Estimated Useful Life Of Assets Table [Table Text Block]	For our unregulated operations, we compute depreciation expense on a straight-line basis over the following estimated useful lives of the assets: Asset Description Useful Life Propane distribution mains 10-37 years Propane bulk plants and tanks 10-40 years Propane equipment, meters and meter installations 5-33 years Measuring and regulating station equipment 5-37 years Natural gas pipelines 45 years Natural gas right of ways Perpetual CHP plant 30 years Natural gas processing equipment 20-25 years Office furniture and equipment 3-10 years Transportation equipment 4-20 years Structures and improvements 5-45 years Other Various

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Calculations of Basic and Diluted Earnings Per Share	The following table presents the calculation of our basic and diluted earnings per share for the years ended December 31: For the Year Ended December 31, 2019 2018 2017 (in thousands, except shares and per share data) Calculation of Basic Earnings Per Share: Income from Continuing Operations $ 61,142 $ 56,862 $ 60,326 Income/(Loss) from Discontinued Operations 4,011 (282 ) (2,202 ) Net Income $ 65,153 $ 56,580 $ 58,124 Weighted average shares outstanding 16,398,443 16,369,616 16,336,789 Earnings Per Share from Continuing Operations $ 3.73 $ 3.48 $ 3.69 Earnings/(Loss) Per Share from Discontinued Operations 0.24 (0.02 ) (0.13 ) Basic Earnings Per Share $ 3.97 $ 3.46 $ 3.56 Calculation of Diluted Earnings Per Share: Reconciliation of Denominator: Weighted average shares outstanding — Basic 16,398,443 16,369,616 16,336,789 Effect of dilutive securities — Share-based compensation 50,043 50,254 46,563 Adjusted denominator — Diluted 16,448,486 16,419,870 16,383,352 Earnings Per Share from Continuing Operations $ 3.72 $ 3.47 $ 3.68 Earnings/(Loss) Per Share from Discontinued Operations 0.24 (0.02 ) (0.13 ) Diluted Earnings Per Share $ 3.96 $ 3.45 $ 3.55

Acquisitions Acquisition (Table

Acquisitions Acquisition (Tables)	12 Months Ended
	Dec. 31, 2019
Acquisition Performance [Abstract]
Schedule of Business Acquisitions, by Acquisition [Table Text Block]	For the year ended December 31, 2019 , these acquisitions generated the following operating revenue and income: For the Year Ended December 31, 2019 Operating Revenues Operating Income (in thousands) Marlin Gas Services $ 5,702 $ 1,500 Ohl propane acquisition $ 1,662 $ 385 Boulden acquisition $ 550 $ 239

Acquisitions Divestitures (Tabl

Acquisitions Divestitures (Tables)	12 Months Ended
	Dec. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Groups, Including Discontinued Operations [Table Text Block]	A summary of discontinued operations presented in the consolidated statements of income includes the following: For the Year Ended December 31, (in thousands) 2019 2018 2017 Operating revenues (1) $ 161,289 $ 258,713 $ 184,519 Cost of sales (1) 157,646 252,111 182,307 Other operating expenses 5,222 6,825 4,522 Operating loss (1,579 ) (223 ) (2,310 ) Interest and other expense 315 297 253 Loss from Discontinued Operations before income taxes (1,894 ) (520 ) (2,563 ) Gain on sale of Discontinued Operations 7,344 — — Income tax (benefit) / expense 1,439 (238 ) (361 ) Gain / (Loss) from Discontinued Operations, Net of Tax $ 4,011 $ (282 ) $ (2,202 ) (1) Included in operating revenues and cost of sales for the years ended December 31, 2019 , 2018 and 2017 , is $19.8 million , $31.5 million and $16.6 million respectively, representing amounts which had been previously eliminated in consolidation related to intercompany activity that will continue with the buyers after the disposition of the assets of PESCO.
Disclosure of Long Lived Assets Held-for-sale [Table Text Block]	The assets and liabilities of the discontinued operations classified as held for sale in the consolidated balance sheet at December 31, 2018 include the following: As of (in thousands) December 31, 2018 Property, plant and equipment $ 1,242 Less: accumulated depreciation (206 ) Net property, plant and equipment (1) 1,036 Current assets (2) 52,681 Deferred charges and other assets (1) 6,626 Assets of Discontinued Operations held for sale $ 60,343 Current liabilities (3) $ 48,672 Liabilities of Discontinued Operations held for sale $ 48,672 Net assets $ 11,671 (1) These balances have been combined within the consolidated balance sheets to arrive at noncurrent assets held for sale. (2) At December 31, 2018 , current assets were primarily comprised of $31.1 million of accounts receivable, $13.1 million of derivative assets at fair value, $4.9 million of accrued revenue and $3.2 million of storage gas prepayments. (3) At December 31, 2018 , current liabilities were primarily comprised of $31.1 million of accounts payable, $13.3 million of derivative liabilities at fair value and $2.7 million of other accrued liabilities.
Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operations Supplemental Cash Flows Schedule [Table Text Block]	The following table summarizes significant statements of cash flows data related to the discontinued operations of PESCO: For the Year Ended December 31, (in thousands) 2019 2018 2017 Depreciation and amortization $ 477 $ 582 $ 213 Property, plant and equipment expenditures — 115 11,766 Deferred income taxes (125 ) 1,088 (1,515 ) Realized / (loss) gain on commodity contracts (2,161 ) 5,002 4,911

Revenue Recognition Revenue R_2

Revenue Recognition Revenue Recognition (Tables)	12 Months Ended
	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue [Table Text Block]	for the years ended December 31, 2019 and 2018 : For the Year Ended December 31, 2019 For the Year Ended December 31, 2018 (in thousands) Regulated Energy Unregulated Energy Other and Eliminations Total Regulated Energy Unregulated Energy Other and Eliminations Total Energy distribution Delaware natural gas division $ 62,659 $ — $ — $ 62,659 $ 70,338 $ — $ — $ 70,338 Florida natural gas division 28,485 — — 28,485 25,341 — — 25,341 FPU electric distribution 77,416 — — 77,416 79,803 — — 79,803 FPU natural gas distribution 82,418 — — 82,418 81,118 — — 81,118 Maryland natural gas division 22,517 — — 22,517 24,172 — — 24,172 Sandpiper natural gas/propane operations 19,068 — — 19,068 22,088 — — 22,088 Total energy distribution 292,563 — — 292,563 302,860 — — 302,860 Energy transmission Aspire Energy — 32,493 — 32,493 — 35,407 — 35,407 Eastern Shore 72,924 — — 72,924 64,248 — — 64,248 Peninsula Pipeline 16,453 — — 16,453 11,927 — — 11,927 Total energy transmission 89,377 32,493 — 121,870 76,175 35,407 — 111,582 Energy generation Eight Flags — 16,749 — 16,749 — 17,302 — 17,302 Propane operations Propane delivery operations — 107,964 — 107,964 — 123,603 — 123,603 Energy delivery services Marlin Gas Services — 5,702 — 5,702 — 121 — 121 Other and eliminations Eliminations (38,934 ) (10,407 ) (18,080 ) (67,421 ) (33,754 ) (16,486 ) (17,522 ) (67,762 ) Other — 1,649 528 2,177 — 1,957 653 2,610 Total other and eliminations (38,934 ) (8,758 ) (17,552 ) (65,244 ) (33,754 ) (14,529 ) (16,869 ) (65,152 ) Total operating revenues (1) $ 343,006 $ 154,150 $ (17,552 ) $ 479,604 $ 345,281 $ 161,904 $ (16,869 ) $ 490,316 (1) Total operating revenues for the year ended December 31, 2019, 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 $0.2 million and $0.3 million for our Regulated and Unregulated Energy segments, respectively, for the year ended December 31, 2018. The sources of other revenues include revenue from alternative revenue programs related to revenue normalization for Maryland division and Sandpiper 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 December 31, 2019 and 2018 were as follows: Trade Receivables Contract Assets (Noncurrent) Contract Liabilities (Current) (in thousands) Balance at 12/31/2018 $ 52,140 $ 2,614 $ 480 Balance at 12/31/2019 47,430 3,465 589 Increase (decrease) $ (4,710 ) $ 851 $ 109
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block]	Revenue for these businesses for the remaining performance obligations at December 31, 2019 are expected to be recognized as follows: (in thousands) 2020 2021 2022 2023 2024 2025 and thereafter Eastern Shore and Peninsula Pipeline $ 37,307 $ 34,000 $ 27,034 $ 21,608 $ 19,385 $ 194,868 Natural gas distribution operations 3,996 4,058 5,100 4,916 4,681 37,149 FPU electric distribution 566 566 566 566 566 1,100 Total revenue contracts with remaining performance obligations $ 41,869 $ 38,624 $ 32,700 $ 27,090 $ 24,632 $ 233,117

Segment Information Segment Inf

Segment Information Segment Information (Tables)	12 Months Ended
	Dec. 31, 2019
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment [Table Text Block]	The following table presents information about our reportable segments. For the Year Ended December 31, 2019 2018 2017 (in thousands) Operating Revenues, Unaffiliated Customers Regulated Energy $ 340,857 $ 343,313 $ 323,972 Unregulated Energy 138,747 147,003 125,674 Total operating revenues, unaffiliated customers $ 479,604 $ 490,316 $ 449,646 Intersegment Revenues (1) Regulated Energy $ 2,149 $ 1,968 $ 2,338 Unregulated Energy 15,403 14,902 14,402 Other businesses 528 652 774 Total intersegment revenues $ 18,080 $ 17,522 $ 17,514 Operating Income Regulated Energy $ 86,584 $ 79,215 $ 74,584 Unregulated Energy 19,939 17,124 14,941 Other businesses and eliminations (236 ) (1,496 ) 205 Operating Income 106,287 94,843 89,730 Other expense, net (1,830 ) (603 ) (2,204 ) Interest charges 22,224 16,146 12,530 Income from Continuing Operations before Income Taxes $ 82,233 $ 78,094 $ 74,996 Income Taxes on Continuing Operations 21,091 21,232 14,670 Income from Continuing Operations 61,142 56,862 60,326 Loss from Discontinued Operations, Net of tax (1,391 ) (282 ) (2,202 ) Gain on sale of Discontinued Operations, Net of tax 5,402 — — Net Income $ 65,153 $ 56,580 $ 58,124 Depreciation and Amortization Regulated Energy $ 35,227 $ 31,876 $ 28,554 Unregulated Energy 10,129 8,263 7,741 Other businesses and eliminations 67 81 91 Total depreciation and amortization $ 45,423 $ 40,220 $ 36,386 Capital Expenditures Regulated Energy $ 130,604 $ 235,912 $ 159,011 Unregulated Energy 60,034 38,585 14,424 Other businesses 8,348 8,364 5,902 Total capital expenditures $ 198,986 $ 282,861 $ 179,337 (1) All significant intersegment revenues are billed at market rates and have been eliminated from consolidated revenues. As of December 31, 2019 2018 Identifiable Assets (1) Regulated Energy segment $ 1,434,066 $ 1,345,805 Unregulated Energy segment (1) 296,810 245,702 Other businesses and eliminations 52,322 41,821 Total identifiable assets (1) $ 1,783,198 $ 1,633,328

Supplemental Cash Flow Disclo_2

Supplemental Cash Flow Disclosures (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Cash Paid for Interest and Income Taxes	Cash paid for interest and income taxes during the years ended December 31, 2019 , 2018 and 2017 were as follows: For the Year Ended December 31, 2019 2018 2017 (in thousands) Cash paid for interest $ 22,611 $ 16,741 $ 12,420 Cash paid for income taxes, net of refunds $ 3,221 $ 477 $ (4,114 )
Non-Cash Investing and Financing Activities	Non-cash investing and financing activities during the years ended December 31, 2019 , 2018 , and 2017 were as follows: For the Year Ended December 31, 2019 2018 2017 (in thousands) Capital property and equipment acquired on account, but not paid for as of December 31 $ 13,470 $ 39,402 $ 15,457 Common stock issued under the SICP $ 1,691 $ 2,006 $ 1,127 Capital lease obligation $ — $ 1,310 $ 2,070

Derivative Instruments (Tables)

Derivative Instruments (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Derivative Instruments [Table Text Block]	As of December 31, 2019 , the volume of our open commodity derivative contracts were as follows: Business unit Commodity Quantity hedged (in millions) Designation Longest expiration date of hedge Sharp Propane (gallons) 9.9 Cash flows hedges June 2022
Schedule of Due to (from) Broker-Dealers and Clearing Organizations [Table Text Block]	(in thousands) Balance Sheet Location December 31, 2019 December 31, 2018 Sharp Other Current Assets $ 2,317 $ 2,173
Fair Values of Derivative Contracts Recorded in Consolidated Balance Sheets	Fair values of the derivative contracts recorded in the consolidated balance sheets as of December 31, 2019 and 2018 are as follows: Derivative Assets Fair Value as of (in thousands) Balance Sheet Location December 31, 2019 December 31, 2018 Derivatives designated as fair value hedges Propane put options Derivative assets, at fair value $ — $ 71 Derivatives designated as cash flow hedges Propane swap agreements Derivative assets, at fair value — 11 Total Derivative Assets $ — $ 82 Derivative Liabilities Fair Value as of (in thousands) Balance Sheet Location December 31, 2019 December 31, 2018 Derivatives designated as cash flow hedges Propane swap agreements Derivative liabilities, at fair value $ 1,844 $ 1,604 Total Derivative Liabilities $ 1,844 $ 1,604
Derivative Instruments, Gain (Loss) [Table Text Block]	The effects of gains and losses from derivative instruments are as follows: Amount of Gain (Loss) on Derivatives: Location of Gain (Loss) on Derivatives For the Year Ended December 31, (in thousands) 2019 2018 2017 Derivatives not designated as hedging instruments Realized gain on forward contracts and options (1) Revenue $ — $ — $ 112 Propane swap agreements Cost of sales — (13 ) 8 Derivatives designated as fair value hedges Put/Call option Cost of sales — — (9 ) Derivatives designated as cash flow hedges Propane swap agreements Cost of sales 1,520 (647 ) 1,607 Propane swap agreements Other comprehensive income (loss) (253 ) (2,773 ) 487 Natural gas swap contracts Other comprehensive income (loss) (63 ) 200 986 Natural gas futures contracts Other comprehensive income (loss) (294 ) 532 (1,476 ) Total $ 910 $ (2,701 ) $ 1,715 (1) All of the realized and unrealized gain (loss) on forward contracts represented the effect of trading activities for Xeron on our consolidated statement of income.

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [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 December 31, 2019 and 2018 , respectively: Fair Value Measurements Using: As of December 31, 2019 Fair Value Quoted Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) (in thousands) Assets: Investments—equity securities $ 27 $ 27 $ — $ — Investments—guaranteed income fund 803 — — 803 Investments—mutual funds and other 8,399 8,399 — — Total investments 9,229 8,426 — 803 Derivative assets — — — — Total assets $ 9,229 $ 8,426 $ — $ 803 Liabilities: Derivative liabilities $ 1,844 $ — $ 1,844 $ — Fair Value Measurements Using: As of December 31, 2018 Fair Value Quoted Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) (in thousands) Assets: Investments—equity securities $ 22 $ 22 $ — $ — Investments—guaranteed income fund 686 — — 686 Investments—mutual funds and other 6,003 6,003 — — Total investments 6,711 6,025 — 686 Derivative assets (1) 82 — 82 — Total assets $ 6,793 $ 6,025 $ 82 $ 686 Liabilities: Derivative liabilities (1) $ 1,604 $ — $ 1,604 $ —
Schedule of Changes in Fair Value of Plan Assets	The following table sets forth the summary of the changes in the fair value of Level 3 investments for the years ended December 31, 2019 and 2018 : For the Year Ended December 31, 2019 2018 (in thousands) Beginning Balance $ 686 $ 648 Purchases and adjustments 131 68 Transfers/disbursements (29 ) (41 ) Investment income 15 11 Ending Balance $ 803 $ 686

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2019
Investments [Abstract]
Investments schedule [Table Text Block]	As of December 31, (in thousands) 2019 2018 Rabbi trust (associated with the Non-Qualified Deferred Compensation Plan) $ 9,202 $ 6,689 Investments in equity securities 27 22 Total $ 9,229 $ 6,711

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Carrying Value of Goodwill	The carrying value of goodwill from continuing operations as of December 31, 2019 and 2018 was as follows: As of December 31, (in thousands) 2019 2018 Goodwill Regulated Energy Florida Natural Gas Distribution (1) $ 3,353 $ 3,353 Unregulated Energy (2) Mid-Atlantic Propane Operations (3) 13,299 2,147 Florida Propane Operations 1,188 1,188 Aspire Energy 10,120 10,120 Marlin Gas Services 4,708 4,760 Total Goodwill $ 32,668 $ 21,568 (1) Florida Natural Gas Distribution includes Chesapeake Utilities' Central Florida Gas division, FPU and FPU's Indiantown and Fort Meade divisions. (2) As discussed in Note 4, Acquisitions and Divestitures , during the fourth quarter of 2019, we sold PESCO's assets and contracts. The goodwill balance for PESCO is reflected as assets held-for-sale in the consolidated balance sheet as of December 31, 2018. (3) Mid-Atlantic Propane Operations goodwill balance includes $11.2 million recognized as a result of the purchase of the operating assets of Boulden in December 2019.
Schedule of Carrying Value and Accumulated Amortization of Intangible Assets	The carrying value and accumulated amortization of intangible assets subject to amortization as of December 31, 2019 and 2018 are as follows: As of December 31, 2019 2018 (in thousands) Gross Carrying Amount Accumulated Amortization Gross Carrying Amount Accumulated Amortization Customer relationships (1) $ 9,391 $ 3,463 $ 4,801 $ 3,066 Non-Compete agreements (1) (2) 2,252 451 1,793 202 Patents 452 118 452 — Other 270 204 270 198 Total $ 12,365 $ 4,236 $ 7,316 $ 3,466

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Schedule of Income Tax Expense	The following tables provide: (a) the components of income tax expense in 2019 , 2018 , and 2017 ; (b) the reconciliation between the statutory federal income tax rate and the effective income tax rate for 2019 , 2018 , and 2017 from continuing operations; and (c) the components of accumulated deferred income tax assets and liabilities at December 31, 2019 and 2018 . For the Year Ended December 31, 2019 2018 2017 (in thousands) Current Income Tax Expense Federal $ (2,271 ) $ 48 $ 2,046 State (492 ) 581 610 Other (47 ) (47 ) (71 ) Total current income tax expense (benefit) (2,810 ) 582 2,585 Deferred Income Tax Expense (1) Property, plant and equipment 25,910 19,189 8,181 Deferred gas costs 79 (1,435 ) 2,002 Pensions and other employee benefits (454 ) 446 180 FPU merger-related premium cost and deferred gain (278 ) (528 ) (1,148 ) Net operating loss carryforwards (3,776 ) (183 ) 193 Other 2,420 3,161 2,677 Total deferred income tax expense 23,901 20,650 12,085 Income Tax Expense from Continuing Operations 21,091 21,232 14,670 Income Tax Expense (benefit) from Discontinued Operations 1,439 (238 ) (361 ) Total Income Tax $ 22,530 $ 20,994 $ 14,309 (1) Includes $4.7 million , $3.5 million , and $0.9 million of deferred state income taxes for the years 2019 , 2018 and 2017 , respectively.
Summary of Reconciliation of Statutory Federal Tax and Effective Income Tax Rates	For the Year Ended December 31, 2019 2018 2017 (in thousands) Reconciliation of Effective Income Tax Rates for Continuing Operations Federal income tax expense (1) $ 17,246 $ 16,491 $ 26,249 State income taxes, net of federal benefit 5,088 4,057 2,000 ESOP dividend deduction (173 ) (158 ) (257 ) Revaluation of deferred tax assets and liabilities — — (14,299 ) Other (1,070 ) 842 977 Total Income Tax Expense for Continuing Operations $ 21,091 $ 21,232 $ 14,670 Effective Income Tax Rate for Continuing Operations (2) 25.65 % 27.19 % 19.56 % (1) Federal income taxes were calculated at 21 percent for 2019 and 2018 and 35 percent for 2017. (2) The effective tax rate for 2017 includes the impact of the revaluation of deferred tax assets and liabilities for our unregulated businesses due to implementation of the TCJA.
Schedule of Accumulated Deferred Income Tax Assets and Liabilities	As of December 31, 2019 2018 (in thousands) Deferred Income Taxes Deferred income tax liabilities: Property, plant and equipment $ 173,466 $ 153,423 Acquisition adjustment 6,969 8,896 Loss on reacquired debt 220 32 Deferred gas costs 1,223 1,139 Natural gas conversion costs 4,956 3,987 Storm reserve liability 10,316 97 Other 1,456 2,544 Total deferred income tax liabilities 198,606 170,118 Deferred income tax assets: Pension and other employee benefits 3,818 3,711 Environmental costs 1,486 1,710 Net operating loss carryforwards 5,523 2,010 Self-insurance 146 151 Storm reserve liability 96 — Other 6,881 5,716 Total deferred income tax assets 17,950 13,298 Deferred Income Taxes Per Consolidated Balance Sheets $ 180,656 $ 156,820

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Outstanding Long-Term Debt	Our outstanding long-term debt is shown below: As of December 31, (in thousands) 2019 2018 FPU secured first mortgage bonds: 9.08% bond, due June 1, 2022 $ 7,990 $ 7,986 Uncollateralized Senior Notes: 5.50% note, due October 12, 2020 2,000 4,000 5.93% note, due October 31, 2023 12,000 15,000 5.68% note, due June 30, 2026 20,300 23,200 6.43% note, due May 2, 2028 6,300 7,000 3.73% note, due December 16, 2028 18,000 20,000 3.88% note, due May 15, 2029 50,000 50,000 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 — 2.98% note, due December 20, 2034 70,000 — Term Note due January 21, 2020 — 30,000 Term Note due February 28, 2020 30,000 — Promissory notes — 26 Finance lease obligations — 1,310 Less: debt issuance costs (822 ) (567 ) Total long-term debt 485,768 327,955 Less: current maturities (45,600 ) (11,935 ) Total long-term debt, net of current maturities $ 440,168 $ 316,020
Schedule of Maturities of Long-term Debt [Table Text Block]	Annual maturities and principal repayments of long-term debt are as follows: Year 2020 2021 2022 2023 2024 Thereafter Total (in thousands) Payments $ 45,600 $ 13,600 $ 25,100 $ 20,600 $ 17,600 $ 364,100 $ 486,600
Line of Credit Facility [Line Items]
Schedule of Line of Credit Facilities [Table Text Block]	The following table summarizes our shelf agreements at December 31, 2019: (in thousands) Total Borrowing Capacity Less Amount of Debt Issued Less Unfunded Commitments Remaining Borrowing Capacity Shelf Agreement Prudential Shelf Agreement (1) $ 220,000 $ (170,000 ) $ — $ 50,000 MetLife Shelf Agreement 150,000 — — 150,000 NYL Shelf Agreement (2) 150,000 (100,000 ) — 50,000 Total $ 520,000 $ (270,000 ) $ — $ 250,000 (1) As described above, in January 2020, we requested and Prudential accepted our request to purchase $50.0 million of our unsecured debt. (2) As described above, in February 2020, we requested and NYL accepted our request to purchase $40.0 million of our unsecured debt.

Short-Term Borrowing Short-Term

Short-Term Borrowing Short-Term Borrowing (Tables)	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Schedule of Short-term Debt	The following table summarizes our short-term borrowing facilities information at December 31, 2019 and 2018 . Outstanding borrowings at (in thousands) Total Facility LIBOR Based Interest Rate December 31, 2019 December 31, 2018 Available at December 31, 2019 Bank Credit Facility Committed revolving credit facility A $ 55,000 plus 0.75 percent $ 55,000 $ 25,000 $ — Committed revolving credit facility B 80,000 plus 0.75 percent 57,150 65,431 22,850 Committed revolving credit facility C 45,000 plus 0.75 percent 42,040 34,672 2,960 Committed revolving credit facility D 40,000 plus 0.85 percent 40,000 40,000 — Committed revolving credit facility E (2) 150,000 plus 1.125 percent 50,000 125,000 100,000 Total short term credit facilities $ 370,000 $ 244,190 $ 290,103 $ 125,810 Book overdrafts (1) 3,181 4,355 Total short-term borrowing $ 247,371 $ 294,458 (1) If presented, these book overdrafts would be funded through the bank revolving credit facilities. (2) This committed revolving credit facility includes a restriction that our short-term borrowings, excluding any borrowings under the committed revolving credit facility, shall not exceed $250.0 million .

Leases Leases (Tables)

Leases Leases (Tables)	12 Months Ended
	Dec. 31, 2019
Leases [Abstract]
Lease, Cost [Table Text Block]	The following table presents information related to our total lease cost included in our consolidated statements of income: Year Ended December 31, ( in thousands) Classification 2019 2018 Operating lease cost (1) Operations expense $ 2,577 $ 3,339 Finance lease cost: Amortization of lease assets Depreciation and amortization 650 1,451 Interest on lease liabilities Interest expense 5 49 Net lease cost $ 3,232 $ 4,839 (1) Includes short-term leases and variable lease costs, which are immaterial.
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 consolidated balance sheet at December 31, 2019 : (in thousands) Balance sheet classification Amount Assets Operating lease assets Operating lease right-of-use assets $ 11,563 Liabilities Current Operating lease liabilities Other accrued liabilities 1,705 Noncurrent Operating lease liabilities Operating lease - liabilities 9,896 Total lease liabilities $ 11,601
Leases, Weighted Average Remaining Lease Term [Table Text Block]	The following table presents our weighted-average remaining lease term and weighted-average discount rate for our operating leases at December 31, 2019 : December 31, 2019 Weighted-average remaining lease term ( in years ) Operating leases 8.88 Weighted-average discount rate Operating leases 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 consolidated statements of cash flows as of December 31, 2019 and 2018 : Year Ended December 31, (in thousands) 2019 2018 Operating cash flows from operating leases $ 2,230 $ 2,759 Operating cash flows from finance leases $ 5 $ 49 Financing cash flows from finance leases $ 650 $ 1,451
Schedule of Future Minimum Lease Payments for Capital Leases [Table Text Block]	The following table presents the future undiscounted maturities of our operating leases at December 31, 2019 and for each of the next five years and thereafter: (in thousands) Operating Leases (1) 2020 $ 2,104 2021 1,866 2022 1,716 2023 1,719 2024 1,463 Thereafter 4,916 Total lease payments 13,784 Less: Interest 2,183 Present value of lease liabilities $ 11,601 (1) Operating lease payments include $3.7 million related to options to extend lease terms that are reasonably certain of being exercised.

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	The following table presents the changes in the balance of accumulated other comprehensive loss for the years ended December 31, 2019 and 2018 . All amounts in the following tables are presented net of tax. Defined Benefit Pension and Postretirement Plan Items Commodity Contract Cash Flow Hedges Total (in thousands) As of December 31, 2017 $ (4,743 ) $ 471 $ (4,272 ) Other comprehensive loss before reclassifications (602 ) (3,130 ) (3,732 ) Amounts reclassified from accumulated other comprehensive income 439 1,759 2,198 Net current-period other comprehensive loss (163 ) (1,371 ) (1,534 ) Stranded tax reclassification to retained earnings (1,022 ) 115 (907 ) As of December 31, 2018 (5,928 ) (785 ) (6,713 ) Other comprehensive income/(loss) before reclassifications (872 ) 2,161 1,289 Amounts reclassified from accumulated other comprehensive income/(loss) 1,867 (2,595 ) (728 ) Net current-period other comprehensive income/(loss) 995 (434 ) 561 Prior-year reclassification — (115 ) (115 ) As of December 31, 2019 $ (4,933 ) $ (1,334 ) $ (6,267 )
Reclassification out of Accumulated Other Comprehensive Income	The following table presents amounts reclassified out of accumulated other comprehensive income (loss) for the years ended December 31, 2019 , 2018 and 2017 . Deferred gains and losses of our commodity contracts cash flow hedges are recognized in earnings upon settlement. For the Year Ended December 31, (in thousands) 2019 2018 2017 Amortization of defined benefit pension and postretirement plan items: Prior service cost (1) $ 77 $ 77 $ 77 Net gain (1) (2,600 ) (579 ) (636 ) Total before income taxes (2,523 ) (502 ) (559 ) Income tax benefit (4) 656 63 223 Net of tax $ (1,867 ) $ (439 ) $ (336 ) Gains and losses on commodity contracts cash flow hedges Propane swap agreements (2) $ 1,520 $ (647 ) $ 1,607 Natural gas swaps (2)(3) 7 197 (822 ) Natural gas futures (2)(3) 2,096 (2,010 ) (456 ) Total before income taxes 3,623 (2,460 ) 329 Income tax impact (4) (1,028 ) 701 (159 ) Net of tax $ 2,595 $ (1,759 ) $ 170 Total reclassifications for the period $ 728 $ (2,198 ) $ (166 ) (1) These amounts are included in the computation of net periodic benefits. See Note 17 , Employee Benefit Plans , for additional details. (2) These amounts are included in the effects of gains and losses from derivative instruments. See Note 8, Derivative Instruments , for additional details.

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2019
Schedule of Assets by Investment Type	The following schedule summarizes the assets of the Chesapeake Pension Plan and the FPU Pension Plan, by investment type, at December 31, 2019 , 2018 and 2017 : Chesapeake Pension Plan FPU Pension Plan At December 31, 2019 2018 2017 2019 2018 2017 Asset Category Equity securities — % 49 % 53 % 53 % 50 % 55 % Debt securities 92 % 41 % 38 % 37 % 41 % 37 % Other 8 % 10 % 9 % 10 % 9 % 8 % Total 100 % 100 % 100 % 100 % 100 % 100 %
Schedule of Asset Allocation Strategy	The following allocation range of asset classes is intended to produce a rate of return sufficient to meet the plans’ goals and objectives (this allocation range applied to Chesapeake Pension Plan prior to the de-risking strategy executed during the fourth quarter of 2019): Asset Allocation Strategy Asset Class Minimum Allocation Percentage Maximum Allocation Percentage Domestic Equities (Large Cap, Mid Cap and Small Cap) 14 % 32 % Foreign Equities (Developed and Emerging Markets) 13 % 25 % Fixed Income (Inflation Bond and Taxable Fixed) 26 % 40 % Alternative Strategies (Long/Short Equity and Hedge Fund of Funds) 6 % 14 % Diversifying Assets (High Yield Fixed Income, Commodities, and Real Estate) 7 % 19 % Cash 0 % 5 %
Summary of Pension Plan Assets	At December 31, 2019 and 2018 , the assets of the Chesapeake Pension Plan and the FPU Pension Plan were comprised of the following investments: Fair Value Measurement Hierarchy At December 31, 2019 At December 31, 2018 Asset Category Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total (in thousands) Mutual Funds - Equity securities U.S. Large Cap (1) $ 3,553 $ — $ — $ 3,553 $ 3,399 $ — $ — $ 3,399 U.S. Mid Cap (1) 1,604 — — 1,604 1,478 — — 1,478 U.S. Small Cap (1) 726 — — 726 670 — — 670 International (2) 9,855 — — 9,855 9,226 — — 9,226 Alternative Strategies (3) 4,739 — — 4,739 5,726 — — 5,726 20,477 — — 20,477 20,499 — — 20,499 Mutual Funds - Debt securities Fixed income (4) 19,220 — — 19,220 18,630 — — 18,630 High Yield (4) 2,476 — — 2,476 2,818 — — 2,818 21,696 — — 21,696 21,448 — — 21,448 Mutual Funds - Other Commodities (5) 1,708 — — 1,708 1,902 — — 1,902 Real Estate (6) 2,288 — — 2,288 2,216 — — 2,216 Guaranteed deposit (7) — — 1,147 1,147 — — 627 627 3,996 — 1,147 5,143 4,118 — 627 4,745 Total Pension Plan Assets in fair value hierarchy $ 46,169 $ — $ 1,147 47,316 $ 46,065 $ — $ 627 46,692 Investments measured at net asset value (8) 7,017 5,558 Total Pension Plan Assets $ 54,333 $ 52,250
Schedule of Level Three Defined Benefit Plan Assets Roll Forward	The following table sets forth the summary of the changes in the fair value of Level 3 investments for the years ended December 31, 2019 and 2018 : For the Year Ended December 31, 2019 2018 (in thousands) Balance, beginning of year $ 627 $ 436 Purchases 2,274 1,674 Transfers in 3,090 2,375 Disbursements (4,907 ) (3,872 ) Investment income 63 14 Balance, end of year $ 1,147 $ 627
Schedule of Amounts Not Yet Reflected in Net Periodic Benefit Cost and Included in Accumulated Other Comprehensive Income Loss or Regulatory Assets	The following table presents the amounts not yet reflected in net periodic benefit cost and included in accumulated other comprehensive loss or as a regulatory asset as of December 31, 2019 : (in thousands) Chesapeake Pension Plan FPU Pension Plan Chesapeake SERP Chesapeake Postretirement Plan FPU Medical Plan Total Prior service cost (credit) $ — $ — $ — $ (447 ) $ — $ (447 ) Net loss (gain) 2,241 19,339 575 604 (32 ) 22,727 Total $ 2,241 $ 19,339 $ 575 $ 157 $ (32 ) $ 22,280 Accumulated other comprehensive loss (gain) pre-tax (1) $ 2,241 $ 3,674 $ 575 $ 157 $ (6 ) $ 6,641 Post-merger regulatory asset — 15,665 — — (26 ) 15,639 Subtotal 2,241 19,339 575 157 (32 ) 22,280 Pre-merger regulatory asset — — — — 6 6 Total unrecognized cost $ 2,241 $ 19,339 $ 575 $ 157 $ (26 ) $ 22,286 (1) The total amount of accumulated other comprehensive loss recorded on our consolidated balance sheet as of December 31, 2019 is net of income tax benefits of $1.7 million .
Schedule of Estimated Future Benefit Payments	The schedule below shows the estimated future benefit payments for each of the plans previously described: Chesapeake Pension Plan (1) FPU Pension Plan (1) Chesapeake SERP (2) Chesapeake Postretirement Plan (2) FPU Medical Plan (2) (in thousands) 2020 $ 115 $ 3,281 $ 151 $ 90 $ 86 2021 $ 368 $ 3,348 $ 150 $ 87 $ 90 2022 $ 106 $ 3,424 $ 148 $ 85 $ 91 2023 $ 927 $ 3,498 $ 146 $ 67 $ 79 2024 $ 111 $ 3,549 $ 144 $ 64 $ 80 Years 2025 through 2029 $ 2,300 $ 18,429 $ 748 $ 264 $ 389 (1) The pension plan is funded; therefore, benefit payments are expected to be paid out of the plan assets. (2) Benefit payments are expected to be paid out of our general funds.
Pension benefit
Schedule of Funded Status of Benefit Obligation and Plan Assets	The following schedules set forth the funded status at December 31, 2019 and 2018 and the net periodic cost for the years ended December 31, 2019 , 2018 and 2017 for the Chesapeake and FPU Pension Plans as well as the Chesapeake SERP: Chesapeake Pension Plan FPU Pension Plan Chesapeake At December 31, 2019 2018 2019 2018 2019 2018 (in thousands) Change in benefit obligation: Benefit obligation — beginning of year $ 10,712 $ 11,443 $ 59,377 $ 64,664 $ 2,285 $ 2,428 Interest cost 375 384 2,452 2,339 74 83 Actuarial loss (gain) 1,443 (610 ) 6,508 (4,739 ) 159 (74 ) Effect of settlement (5,833 ) — — — — — Benefits paid (483 ) (505 ) (3,033 ) (2,887 ) (361 ) (152 ) Benefit obligation — end of year 6,214 10,712 65,304 59,377 2,157 2,285 Change in plan assets: Fair value of plan assets — beginning of year 8,649 9,350 43,601 48,396 — — Actual return on plan assets 1,180 (647 ) 7,978 (3,113 ) — — Employer contributions 1,117 451 1,157 1,205 361 152 Effect of settlement (5,833 ) — — — — Benefits paid (483 ) (505 ) (3,033 ) (2,887 ) (361 ) (152 ) Fair value of plan assets — end of year 4,630 8,649 49,703 43,601 — — Reconciliation: Funded status (1,584 ) (2,063 ) (15,601 ) (15,776 ) (2,157 ) (2,285 ) Accrued pension cost $ (1,584 ) $ (2,063 ) $ (15,601 ) $ (15,776 ) $ (2,157 ) $ (2,285 ) Assumptions: Discount rate 3.00 % 4.00 % 3.25 % 4.25 % 3.00 % 4.00 % Expected return on plan assets 6.00 % 6.00 % 6.50 % 6.50 % — % — %
Component of Net Periodic Pension Cost (Benefit)	Chesapeake FPU Chesapeake For the Years Ended December 31, 2019 (1) 2018 2017 2019 2018 2017 2019 2018 2017 (in thousands) Components of net periodic pension cost: Interest cost $ 375 $ 384 $ 402 $ 2,452 $ 2,339 $ 2,482 $ 74 $ 83 $ 89 Expected return on assets (487 ) (542 ) (495 ) (2,770 ) (3,091 ) (2,779 ) — — — Amortization of actuarial loss 391 343 399 505 404 513 85 101 87 Settlement expense 1,982 — — — — — 58 — — Net periodic pension cost 2,261 185 306 187 (348 ) 216 217 184 176 Amortization of pre-merger regulatory asset — — — 543 761 761 — — — Total periodic cost $ 2,261 $ 185 $ 306 $ 730 $ 413 $ 977 $ 217 $ 184 $ 176 Assumptions: Discount rate 3.00 % 3.50 % 3.75 % 4.25 % 3.75 % 4.00 % 4.00 % 3.50 % 3.75 % Expected return on plan assets 6.00 % 6.00 % 6.00 % 6.50 % 6.50 % 6.50 % — % — % — %
Other Postretirement Benefit Plans
Schedule of Funded Status of Benefit Obligation and Plan Assets	The following table sets forth the funded status at December 31, 2019 and 2018 : Chesapeake FPU At December 31, 2019 2018 2019 2018 (in thousands) Change in benefit obligation: Benefit obligation — beginning of year $ 1,002 $ 1,128 $ 1,187 $ 1,287 Interest cost 39 38 48 47 Plan participants contributions 149 136 38 41 Actuarial loss (gain) 73 (131 ) 47 (89 ) Benefits paid (163 ) (169 ) (96 ) (99 ) Benefit obligation — end of year 1,100 1,002 1,224 1,187 Change in plan assets: Fair value of plan assets — beginning of year — — — — Employer contributions (1) 14 33 58 58 Plan participants contributions 149 136 38 41 Benefits paid (163 ) (169 ) (96 ) (99 ) Fair value of plan assets — end of year — — — — Reconciliation: Funded status (1,100 ) (1,002 ) (1,224 ) (1,187 ) Accrued postretirement cost $ (1,100 ) $ (1,002 ) $ (1,224 ) $ (1,187 ) Assumptions: Discount rate 3.00 % 4.00 % 3.25 % 4.25 % (1) The Chesapeake Postretirement Plan does not receive a Medicare Part-D subsidy. The FPU Medical Plan did not receive a significant subsidy for the post-merger period.
Component of Net Periodic Pension Cost (Benefit)	Net periodic postretirement benefit costs for 2019 , 2018 , and 2017 include the following components: Chesapeake FPU For the Years Ended December 31, 2019 2018 2017 2019 2018 2017 (in thousands) Components of net periodic postretirement cost: Interest cost $ 39 $ 38 $ 41 $ 48 $ 47 $ 50 Amortization of actuarial loss 46 58 53 — — — Amortization of prior service cost (credit) (77 ) (77 ) (77 ) — — — Net periodic cost 8 19 17 48 47 50 Amortization of pre-merger regulatory asset — — — 8 8 8 Total periodic cost $ 8 $ 19 $ 17 $ 56 $ 55 $ 58 Assumptions Discount rate 4.00 % 3.50 % 3.75 % 4.25 % 3.75 % 4.00 %

Share-Based Compensation Plans

Share-Based Compensation Plans (Tables)	12 Months Ended
	Dec. 31, 2019
Share-Based Compensation Amounts Included in Net Income	The table below presents the amounts included in net income related to share-based compensation expense for the awards granted under the SICP for the years ended December 31, 2019 , 2018 and 2017 : For the Year Ended December 31, 2019 2018 2017 (in thousands) Awards to non-employee directors $ 620 $ 539 $ 540 Awards to key employees 3,659 2,871 1,950 Total compensation expense 4,279 3,410 2,490 Less: tax benefit (1,117 ) (934 ) (1,003 ) Share-based compensation amounts included in net income $ 3,162 $ 2,476 $ 1,487
Cash Proceeds Received and Tax Benefit from Share-based Payment Awards [Table Text Block]	The below table presents the number of shares withheld, amounts remitted to taxing authorities and the tax benefits associated with these obligations: For the Year Ended December 31, 2019 2018 2017 (amounts except shares, in thousands) Shares withheld to satisfy tax obligations 7,635 16,918 10,269 Amounts remitted to tax authorities to satisfy obligations $ 692 $ 1,210 $ 692 Tax benefit associated with settlement of share based payments $ — $ — $ 349
SICP Awards to Key Employees
Summary of Stock Activity Non-employee directors	The table below presents the summary of the stock activity for awards to key employees: Number of Shares Weighted Average Fair Value Outstanding — December 31, 2017 132,642 $ 59.31 Granted 49,494 67.76 Vested (29,786 ) 47.39 Vested - Accelerated pursuant to separation agreement (16,676 ) 75.78 Expired (3,933 ) 49.66 Outstanding — December 31, 2018 131,741 67.24 Granted (1) 88,048 92.74 Vested (25,831 ) 67.08 Expired (15,086 ) 69.28 Forfeited (2) (21,055 ) 71.67 Outstanding — December 31, 2019 157,817 $ 80.28

Rates and Other Regulatory Ac_2

Rates and Other Regulatory Activities Summary of Effects of Tax Reform Impact on Regulated Businesses (Tables)	12 Months Ended
	Dec. 31, 2019
Summary of Effects of Federal Tax Reform on Regulated Businesses [Abstract]
Summary of Effects of Federal Tax Reform on Regulated Businesses [Table Text Block]	Summary TCJA Table Regulatory Liabilities related to ADIT Operation and Regulatory Jurisdiction Amount (in thousands) Status Status of Customer Rate impact related to lower federal corporate income tax rate Eastern Shore (FERC) $34,190 Will be addressed in Eastern Shore's next rate case filing. Implemented one-time bill credit (totaling $0.9 million) in April 2018. Customer rates were adjusted in April 2018. Delaware Division (Delaware PSC) $12,847 PSC approved amortization of ADIT in January 2019. Implemented one-time bill credit (totaling $1.5 million) in April 2019. Customer rates were adjusted in March 2019. Maryland Division (Maryland PSC) $4,087 PSC approved amortization of ADIT in May 2018. Implemented one-time bill credit (totaling $0.4 million) in July 2018. Customer rates were adjusted in May 2018. Sandpiper Energy (Maryland PSC) $3,765 PSC approved amortization of ADIT in May 2018. Implemented one-time bill credit (totaling $0.6 million) in July 2018. Customer rates were adjusted in May 2018. Chesapeake Florida Gas Division/Central Florida Gas (Florida PSC) $8,304 PSC issued order authorizing amortization and retention of net ADIT liability by the Company in February 2019. Florida PSC's final order was issued in February 2019. Excluding GRIP, tax savings arising from the TCJA rate reduction will be retained by the Company. FPU Natural Gas (excludes Fort Meade and Indiantown) (Florida PSC) $19,218 Same treatment on a net basis as Chesapeake Florida Gas Division (above). Same treatment on a net basis as Chesapeake Florida Gas Division (above). FPU Fort Meade and Indiantown Divisions $294 Same treatment on a net basis as Chesapeake Florida Gas Division (above). Tax rate reduction: The impact was immaterial for the divisions. FPU Electric (Florida PSC) $5,769 In January 2019, PSC issued order approving amortization of ADIT through purchased power cost recovery, storm reserve and rates. TCJA benefit will flow back to its customers through a combination of reductions to the fuel cost recovery rate, base rates, as well as application to the storm reserve over the next several years.

Rates and Other Regulatory Ac_3

Rates and Other Regulatory Activities Regulatory assets and liabilities (Tables)	12 Months Ended
	Dec. 31, 2019
Regulated Operations [Abstract]
Schedule of Regulatory Assets [Table Text Block]	At December 31, 2019 and 2018 , our regulated utility operations had recorded the following regulatory assets and liabilities included in our consolidated balance sheets. These assets and liabilities will be recognized as revenues and expenses in future periods as they are reflected in customers’ rates. As of December 31, 2019 2018 (in thousands) Regulatory Assets Under-recovered purchased fuel and conservation cost recovery (1) $ 5,144 $ 4,631 Under-recovered GRIP revenue (2) — 165 Deferred postretirement benefits (3) 16,311 15,517 Deferred conversion and development costs (1) 20,881 16,727 Environmental regulatory assets and expenditures (4) 2,241 2,731 Acquisition adjustment (5) 30,329 33,255 Loss on reacquired debt (6) 869 942 Other 2,776 3,250 Total Regulatory Assets $ 78,551 $ 77,218 Regulatory Liabilities Self-insurance (7) $ 873 $ 947 Over-recovered purchased fuel and conservation cost recovery (1) 2,724 5,856 Over-recovered GRIP revenue (2) 2,668 1,563 Storm reserve (7) 1,437 677 Accrued asset removal cost (8) 36,767 42,401 Deferred income taxes due to rate change (9) 89,191 91,236 Other 75 242 Total Regulatory Liabilities $ 133,735 $ 142,922 (1) We are allowed to recover the asset or are required to pay the liability in rates. We do not earn an overall rate of return on these assets. (2) The Florida PSC allowed us to recover through a surcharge, capital and other program-related-costs, inclusive of an appropriate return on investment, associated with accelerating the replacement of qualifying distribution mains and services (defined as any material other than coated steel or plastic) in FPU’s natural gas distribution, Fort Meade division and Chesapeake Utilities’ Central Florida Gas division. We are allowed to recover the asset or are required to pay the liability in rates related to GRIP. (3) The Florida PSC allowed FPU to treat as a regulatory asset the portion of the unrecognized costs pursuant to ASC Topic 715 , Compensation - Retirement Benefits , related to its regulated operations. In 2019, we recorded as a regulatory asset the portion of pension settlement expense associated with the de-risking of the Chesapeake Pension Plan pursuant to an order from the FERC that allowed us to defer Eastern Shore's portion. See Note 17 , Employee Benefit Plans, for additional information. (4) All of our environmental expenditures incurred to date and our current estimate of future environmental expenditures have been approved by various PSCs for recovery. See Note 20 , Environmental Commitments and Contingencies , for additional information on our environmental contingencies. (5) We are allowed to include the premiums paid in various natural gas utility acquisitions in Florida in our rate bases and recover them over a specific time period pursuant to the Florida PSC approvals. We paid $34.2 million of the premium in 2009, including a gross up for income tax, because it is not tax deductible, and $0.7 million of the premium paid by FPU in 2010. (6) Gains and losses resulting from the reacquisition of long-term debt are amortized over future periods as adjustments to interest expense in accordance with established regulatory practice. (7) We have self-insurance and storm reserves in our Florida regulated energy operations that allow us to collect through rates amounts to be used against general claims, storm restoration costs and other losses as they are incurred. (8) See Note 1 , Summary of Significant Accounting Policies, for additional information on our asset removal cost policies. (9) We recorded a regulatory liability for our regulated businesses related to the revaluation of accumulated deferred tax assets/liabilities as a result of the TCJA. Based upon the regulatory proceedings, we will pass back the respective portion of the excess accumulated deferred taxes to rate payers. See Note 12, Income Taxes , for additional information.

Environmental Commitments and_2

Environmental Commitments and Contingencies Environmental Remediation Status (Tables)	12 Months Ended
	Dec. 31, 2019
Environmental Remediation Obligations [Abstract]
Schedule of Environmental Loss Contingencies by Site [Table Text Block]	The following is a summary of our remediation status and estimated costs to implement clean-up of our key MGP sites: MGP Site (Jurisdiction) Status Estimated Cost to Clean Up (Expect to Recover through Rates) West Palm Beach (Florida) Remedial actions approved by the Florida Department of Environmental Protection have been implemented on the east parcel of the site. We expect to implement similar remedial actions on the site's west parcel in 2020. Between $4.5 million to $15.4 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. Sanford (Florida) In March 2018, the United States Environmental Protection Agency ("EPA") approved a "site-wide ready for anticipated use" status, which is the final step before delisting a site. Construction has been completed and restrictive covenants are in place to ensure protection of human health. The only remaining activity is long-term groundwater monitoring. FPU's remaining remediation expenses, including attorneys' fees and costs, are anticipated to be immaterial. Winter Haven (Florida) Remediation is ongoing. Not expected to exceed $0.4 million. Seaford (Delaware) Conducted investigations of on-site and off-site impacts in the vicinity of the site, from 2014 through 2018, and submitted the findings to Delaware Department of Natural Resources and Environmental Control ("DNREC") in a March 2019 report. An interim action involving air-sparging/vapor extraction is being implemented, in accordance with the DNREC-approved Work Plan. Between $0.2 million and $0.5 million.

Other Commitments and Conting_2

Other Commitments and Contingencies Other Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2019
Long-term Purchase Commitment [Line Items]
Long-term Purchase Commitment [Table Text Block]	The total purchase obligations for natural gas, electric and propane supplies are as follows: Year 2020 2021-2022 2023-2024 Beyond 2024 Total (in thousands) Purchase Obligations $ 60,735 $ 72,123 $ 60,049 $ 201,131 $ 394,038

Quarterly Financial Data (Table

Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2019
Text Block [Abstract]
Schedule of Quarterly Financial Information	Due to the seasonal nature of our business, there are substantial variations in operations reported on a quarterly basis. For the Quarters Ended March 31 June 30 September 30 December 31 (in thousands except per share amounts) 2019 (1) Operating Revenues $ 160,464 $ 94,541 $ 92,626 $ 131,973 Operating Income $ 44,123 $ 18,164 $ 14,358 $ 29,642 Net Income: Income from Continuing Operations $ 28,814 $ 8,913 $ 6,246 $ 17,169 Loss from Discontinued Operations, Net of Tax (149 ) (609 ) (624 ) (9 ) Gain on sale of Discontinued Operations, Net of Tax — — — 5,402 $ 28,665 $ 8,304 $ 5,622 $ 22,562 Basic Earnings Per Share of Common Stock: Earnings Per Share from Continuing Operations $ 1.76 $ 0.54 $ 0.38 $ 1.05 Earnings/(Loss) Per Share from Discontinued Operations (0.01 ) (0.03 ) (0.04 ) 0.33 $ 1.75 $ 0.51 $ 0.34 $ 1.38 Diluted Earnings Per Share of Common Stock: Earnings Per Share from Continuing Operations $ 1.75 $ 0.54 $ 0.38 $ 1.04 Earnings/(Loss) Per Share from Discontinued Operations (0.01 ) (0.04 ) (0.04 ) 0.33 $ 1.74 $ 0.50 $ 0.34 $ 1.37 2018 (1) Operating Revenues $ 168,831 $ 93,872 $ 93,400 $ 134,214 Operating Income $ 40,853 $ 12,238 $ 12,879 $ 28,873 Net Income: Income from Continuing Operations $ 27,271 $ 5,705 $ 6,090 $ 17,796 Income/(Loss) from Discontinued Operations (415 ) 680 (552 ) 5 $ 26,856 $ 6,385 $ 5,538 $ 17,801 Basic Earnings Per Share of Common Stock: Earnings Per Share from Continuing Operations $ 1.67 $ 0.35 $ 0.37 $ 1.09 Earnings/(Loss) Per Share from Discontinued Operations (0.03 ) 0.04 (0.03 ) — $ 1.64 $ 0.39 $ 0.34 $ 1.09 Diluted Earnings Per Share of Common Stock: Earnings Per Share from Continuing Operations $ 1.66 $ 0.35 $ 0.37 $ 1.09 Earnings/(Loss) Per Share from Discontinued Operations (0.02 ) 0.04 (0.04 ) — $ 1.64 $ 0.39 $ 0.33 $ 1.09 (1) The sum of the four quarters does not equal the total for the year due to rounding.

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Summary of Property, Plant and Equipment by Classification (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)mi	Dec. 31, 2018USD ($)mi
Property, Plant and Equipment [Line Items]
Contributions in Aid of Construction	$ 2,100	$ 2,800
Public Utilities, Allowance for Funds Used During Construction, Description	$ 700	1,900
Number of Months to Establish ROU Asset and Liability	12 months
Property, plant and equipment
Total property, plant and equipment	$ 1,746,532	1,568,441
Less: Accumulated depreciation and amortization	(336,876)	(294,089)
Plus: Construction work in progress	54,141	79,168
Net property, plant and equipment	1,463,797	1,353,520
Natural Gas Distribution [Member] | Delmarva and Florida [Member]
Property, plant and equipment
Total property, plant and equipment	705,095	657,630
Natural Gas Transmission [Member] | Delmarva Peninsula, Pennsylvania and Florida [Member]
Property, plant and equipment
Total property, plant and equipment	608,727	537,654
Natural Gas Transmission [Member] | OHIO
Property, plant and equipment
Total property, plant and equipment	73,658	70,225
Electric distribution | Florida
Property, plant and equipment
Total property, plant and equipment	127,651	102,133
Propane Operations [Member] | Mid-Atlantic and Florida [Member]
Property, plant and equipment
Total property, plant and equipment	141,841	123,632
Electricity and Steam Generation [Member] | Florida
Property, plant and equipment
Total property, plant and equipment	35,436	35,239
Mobile CNG Utility and Pipeline Solutions [Member] | Florida
Property, plant and equipment
Total property, plant and equipment	14,014	7,240
Other unregulated energy | Other [Member]
Property, plant and equipment
Total property, plant and equipment	104	104
Other
Property, plant and equipment
Total property, plant and equipment	40,006	34,584
Natural Gas Operations [Member]
Property, plant and equipment
Less: Accumulated depreciation and amortization	(1,500)	$ (1,400)
Net property, plant and equipment	$ 6,700
Miles Of Natural Gas Pipeline | mi	26	16

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)utilitymi	Dec. 31, 2018USD ($)mi	Dec. 31, 2017USD ($)
Summary Of Accounting Policies [Line Items]
Number of Months to Establish ROU Asset and Liability	12 months
Operating Lease, Liability	$ 11,601
Number of Utilities that do not have cost recovery mechanism	1
Delay of Revenue Recognition Due To Implementation of New Standard | utility	2
Maturity Period To Be Considered Cash Equivalents	3 months
Contributions or Advances in Aid of Construction	$ 2,100	$ 2,800
Net property, plant and equipment	1,463,797	1,353,520
Accumulated depreciation	336,876	294,089
Depreciation and accretion reported in operations expenses	8,800	8,500	$ 8,100
Gain from a settlement	(130)	$ (130)	$ (130)
Operating Lease, Right-of-Use Asset	11,563
Natural Gas Operations
Summary Of Accounting Policies [Line Items]
Net property, plant and equipment	$ 6,700
Length of pipeline | mi	26	16
Ownership interest	45.00%
Accumulated depreciation	$ 1,500	$ 1,400
Minimum [Member]
Summary Of Accounting Policies [Line Items]
Operating Lease, Liability	11,000
Maximum
Summary Of Accounting Policies [Line Items]
Operating Lease, Liability	$ 13,000

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Average Depreciation Rates (Detail)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Natural gas distribution | Delmarva
Property, Plant and Equipment [Line Items]
Average depreciation rates	2.50%	2.50%	2.50%
Natural gas distribution | Florida
Property, Plant and Equipment [Line Items]
Average depreciation rates	2.60%	2.90%	2.90%
Natural gas transmission | Delmarva
Property, Plant and Equipment [Line Items]
Average depreciation rates	2.60%	2.70%	2.80%
Natural gas transmission | Florida
Property, Plant and Equipment [Line Items]
Average depreciation rates	2.40%	2.30%	3.50%
Electric distribution | Florida
Property, Plant and Equipment [Line Items]
Average depreciation rates	3.40%	3.40%	3.40%

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Estimated Useful Lives of Assets (Detail)	12 Months Ended
	Dec. 31, 2019
Propane Distribution Mains [Member] | Minimum
Useful Life of Assets	10 years
Propane Distribution Mains [Member] | Maximum
Useful Life of Assets	37 years
Propane Bulk Plants And Tanks [Member] | Minimum
Useful Life of Assets	10 years
Propane Bulk Plants And Tanks [Member] | Maximum
Useful Life of Assets	40 years
Liquefied Petroleum Gas Equipment [Member] | Minimum
Useful Life of Assets	5 years
Liquefied Petroleum Gas Equipment [Member] | Maximum
Useful Life of Assets	33 years
Meters And Meter Installations [Member] | Minimum
Useful Life of Assets	5 years
Meters And Meter Installations [Member] | Maximum
Useful Life of Assets	33 years
Measuring And Regulating Station Equipment [Member] | Minimum
Useful Life of Assets	5 years
Measuring And Regulating Station Equipment [Member] | Maximum
Useful Life of Assets	37 years
Natural gas pipelines [Member] | Maximum
Useful Life of Assets	45 years
Natural gas processing equipment [Member] | Minimum
Useful Life of Assets	20 years
Natural gas processing equipment [Member] | Maximum
Useful Life of Assets	25 years
Office Furniture And Equipment [Member] | Minimum
Useful Life of Assets	3 years
Office Furniture And Equipment [Member] | Maximum
Useful Life of Assets	10 years
Transportation Equipment [Member] | Minimum
Useful Life of Assets	4 years
Transportation Equipment [Member] | Maximum
Useful Life of Assets	20 years
Structures And Improvements [Member] | Minimum
Useful Life of Assets	5 years
Structures And Improvements [Member] | Maximum
Useful Life of Assets	45 years

Earnings Per Share - Calculatio

Earnings Per Share - Calculations of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Earnings Per Share Calculations Of Basic And Diluted Earnings Per Share [Abstract]
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent	$ 17,169	$ 6,246	$ 8,913	$ 28,814	$ 17,796	$ 6,090	$ 5,705	$ 27,271	$ 61,142	$ 56,862	$ 60,326
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax									$ 4,011	$ (282)	$ (2,202)
Income (Loss) from Continuing Operations, Per Basic Share	$ 1.05	$ 0.38	$ 0.54	$ 1.76	$ 1.09	$ 0.37	$ 0.35	$ 1.67	$ 3.73	$ 3.48	$ 3.69
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share	$ 0.33	$ (0.04)	$ (0.03)	$ (0.01)	$ 0	$ (0.03)	$ 0.04	$ (0.03)	$ 0.24	$ (0.02)	$ (0.13)
Calculation of Basic Earnings Per Share:
Net Income	$ 22,562	$ 5,622	$ 8,304	$ 28,665	$ 17,801	$ 5,538	$ 6,385	$ 26,856	$ 65,153	$ 56,580	$ 58,124
Weighted shares outstanding - Basic (in shares)									16,398,443	16,369,616	16,336,789
Basic Earnings Per Share (in usd per share)	$ 1.38	$ 0.34	$ 0.51	$ 1.75	$ 1.09	$ 0.34	$ 0.39	$ 1.64	$ 3.97	$ 3.46	$ 3.56
Calculation of Diluted Earnings Per Share:
Net Income	$ 22,562	$ 5,622	$ 8,304	$ 28,665	$ 17,801	$ 5,538	$ 6,385	$ 26,856	$ 65,153	$ 56,580	$ 58,124
Reconciliation of Denominator:
Weighted shares outstanding - Basic (in shares)									16,398,443	16,369,616	16,336,789
Share-based Compensation									50,043	50,254	46,563
Adjusted denominator — Diluted									16,448,486	16,419,870	16,383,352
Income (Loss) from Continuing Operations, Per Diluted Share	$ 1.37	$ 0.38	$ 0.54	$ 1.75	$ 1.09	$ 0.37	$ 0.35	$ 1.66	$ 3.72	$ 3.47	$ 3.68
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax, Per Diluted Share	1.04	(0.04)	(0.04)	(0.01)	0	(0.04)	0.04	(0.02)	0.24	(0.02)	(0.13)
Diluted (in usd per share)	$ 0.33	$ 0.34	$ 0.50	$ 1.74	$ 1.09	$ 0.33	$ 0.39	$ 1.64	$ 3.96	$ 3.45	$ 3.55

Acquisitions - Additional Infor

Acquisitions - Additional Information (Detail) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019USD ($)	Sep. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)Dekatherm	Dec. 31, 2017USD ($)
Cash paid for acquisition									$ 23,988	$ 16,654	$ 11,945
Revenues	$ 131,973	$ 92,626	$ 94,541	$ 160,464	$ 134,214	$ 93,400	$ 93,872	$ 168,831	479,604	490,316	449,646
Operating Income (Loss)	29,642	14,358	18,164	44,123	28,873	12,879	12,238	40,853	106,287	94,843	89,730
Net Income	22,562	$ 5,622	$ 8,304	$ 28,665	17,801	$ 5,538	$ 6,385	$ 26,856	65,153	$ 56,580	58,124
Marlin Gas Services [Member]
Revenues									5,702
Operating Income (Loss)									1,500
Additional Compressed Natural Gas Deliverability | Dekatherm										7,000
Boulden [Member]
Revenues									550
Operating Income (Loss)									239
Business Combination, Consideration Transferred									24,600
Marlin and Ohl [Member]
Business Combination, Consideration Transferred										$ 18,200
ARM Energy [Member]
Business Combination, Liabilities Arising from Contingencies, Amount Recognized									2,500
Ohl [Member]
Public Utilities, Property, Plant and Equipment, Amount of Acquisition Adjustments					$ 200					200
Regulated Energy [Member]
Operating Income (Loss)									$ 86,584	79,215	74,584
Regulated Energy [Member] | Elkton Gas [Member]
Number of customers acquired through acquisition									7,000
Unregulated Energy
Operating Income (Loss)									$ 19,939	17,124	$ 14,941
Unregulated Energy | Boulden [Member]
Number of customers acquired through acquisition									5,200
Business Combination, Working Capital	200								$ 200
Business Combination, Contingent Consideration, Liability	600								600
Property, Plant and Equipment, Acquired During Period	8,300								8,300
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	$ 5,100								5,100
Goodwill, Acquired During Period									11,200
Unregulated Energy | Marlin [Member]
Goodwill, Acquired During Period										$ 4,800
Unregulated Energy | Ohl [Member]
Revenues									1,662
Operating Income (Loss)									$ 385
Number of customers acquired through acquisition										2,500
Goodwill, Acquired During Period										$ 1,500

Acquisitions Divestitures (Deta

Acquisitions Divestitures (Details) $ in Thousands		12 Months Ended
		Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Transactions		4
Accrued Revenue		$ 20,846	$ 22,640
Proceeds from the sale of discontinued operations		22,871
Depreciation and amortization		477	582	$ 213
Property, plant and equipment	[1]		1,036
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment		(336,876)	(294,089)
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment, Noncurrent			1,242
Disposal Group, Including Discontinued Operation, Revenue	[2]	161,289	258,713	184,519
Disposal Group, Including Discontinued Operation, Costs of Goods Sold	[2]	157,646	252,111	182,307
Disposal Group, Including Discontinued Operation, Operating Expense		5,222	6,825	4,522
Disposal Group, Including Discontinued Operation, Operating Income (Loss)		(1,579)	(223)	(2,310)
Disposal Group, Including Discontinued Operation, Interest Expense		315	297	253
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax		(1,894)	(520)	(2,563)
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax		7,344	0	0
Discontinued Operation, Tax Effect of Discontinued Operation		1,439	238	361
Gain Loss From Discontinued Operations			(282)	(2,202)
Disposal Group, Including Discontinued Operation, Assets, Current		134,826	191,537
Disposal Group, Including Discontinued Operation, Other Assets	[1]		6,626
Disposal Group, Including Discontinued Operation, Assets			60,343
Disposal Group, Including Discontinued Operation, Liabilities	[3]		48,672
Deferred Income Tax Expense (Benefit)	[4]	23,901	20,650	12,085
Discontinued Operations, Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain Loss From Discontinued Operations		4,011
Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Business Combination, Working Capital		8,000
Capital Expenditure, Discontinued Operations			115	11,766
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment			(206)
Disposal Group, Including Discontinued Operation, Assets, Current	[5]		52,681
Deferred Income Tax Expense (Benefit)		(125)	1,088	(1,515)
Settlement Gain		(2,161)	5,002	4,911
Net Assets			11,671
PESCO [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Intra-Entity Amounts, Discontinued Operation after Disposal, Revenue		$ 19,800	31,500	$ 16,600
Accounts Receivable, before Allowance for Credit Loss, Current			31,100
Derivative Asset			13,100
Accrued Revenue			4,900
Prepaid Expense			3,200
Accounts Payable			31,100
Derivative Liability			13,300
Other Liabilities			$ 2,700
[1]	These balances have been combined within the consolidated balance sheets to arrive at noncurrent assets held for sale.
[2]	) Included in operating revenues and cost of sales for the years ended December 31, 2019 , 2018 and 2017 , is $19.8 million , $31.5 million and $16.6 million respectively, representing amounts which had been previously eliminated in consolidation related to intercompany activity that will continue with the buyers after the disposition of the assets of PESCO.
[3]	(3) At December 31, 2018 , current liabilities were primarily comprised of $31.1 million of accounts payable, $13.3 million of derivative liabilities at fair value and $2.7 million of other accrued liabilities.
[4]	(1) Includes $4.7 million , $3.5 million , and $0.9 million of deferred state income taxes for the years 2019 , 2018 and 2017 , respectively.
[5]	At December 31, 2018 , current assets were primarily comprised of $31.1 million of accounts receivable, $13.1 million of derivative assets at fair value, $4.9 million of accrued revenue and $3.2 million

Revenue Recognition Contract Ba

Revenue Recognition Contract Balances (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Receivables from Customers	$ 47,430	$ 52,140
Contract with Customer, Asset, Net, Noncurrent	3,465	2,614
Contract with Customer, Liability, Current	589	480
Increase (Decrease) in Receivables	(4,710)
Increase (Decrease) in Other Noncurrent Assets	851
Increase (Decrease) in Other Current Liabilities	109
Contract with Customer, Liability, Revenue Recognized	$ 1,000	$ 700

Revenue Recognition Disaggregat

Revenue Recognition Disaggregation of Revenue (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Revenues	$ 131,973,000	$ 92,626,000	$ 94,541,000	$ 160,464,000	$ 134,214,000	$ 93,400,000	$ 93,872,000	$ 168,831,000	$ 479,604,000	$ 490,316,000	$ 449,646,000
Revenue from Contract with Customer, Excluding Assessed Tax									479,604,000	490,316,000
Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									2,177,000	2,610,000
Energy Transmission [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									121,870,000	111,582,000
Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									(67,421,000)	(67,762,000)
Regulated Energy
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									343,006,000	345,281,000
Regulated Energy | Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									0
Regulated Energy | Energy Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									292,563,000	302,860,000
Regulated Energy | Energy Transmission [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									89,377,000	76,175,000
Regulated Energy | Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									(38,934,000)	(33,754,000)
Unregulated Energy
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									154,150,000	161,904,000
Unregulated Energy | Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									1,649,000	1,957,000
Unregulated Energy | Energy Transmission [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									32,493,000	35,407,000
Unregulated Energy | Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									(10,407,000)	(16,486,000)
Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									(17,552,000)	(16,869,000)
Other Segments And Intersegments Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									(17,552,000)	(16,869,000)
Other Segments And Intersegments Eliminations [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									528,000	653,000
Other Segments And Intersegments Eliminations [Member] | Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									(18,080,000)	(17,522,000)
Consolidation, Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									(65,244,000)	(65,152,000)
Other [Member] | Regulated Energy
Disaggregation of Revenue [Line Items]
Revenues									(100,000)	200,000
Other [Member] | Unregulated Energy
Disaggregation of Revenue [Line Items]
Revenues									300,000	300,000
Florida Natural Gas Distribution [Member] | Regulated Energy | Energy Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									62,659,000	70,338,000
Delaware natural gas division [Member] | Regulated Energy | Energy Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									28,485,000	25,341,000
FPU Electric Distribution [Member] | Regulated Energy | Energy Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									77,416,000	79,803,000
Florida Public Utilities Company [Member] | Regulated Energy | Energy Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									82,418,000	81,118,000
Maryland Natural Gas [Member] | Regulated Energy | Energy Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									22,517,000	24,172,000
Sandpiper [Member] | Regulated Energy | Energy Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									19,068,000	22,088,000
Aspire [Member] | Unregulated Energy | Energy Transmission [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									32,493,000	35,407,000
Eastern Shore Gas Company [Member] | Regulated Energy | Energy Transmission [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									72,924,000	64,248,000
Peninsula Pipeline [Member] | Regulated Energy | Energy Transmission [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									16,453,000	11,927,000
Eight Flags [Member] | Unregulated Energy | Energy Generation [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									16,749,000	17,302,000
Florida Propane [Member] | Unregulated Energy | Propane Delivery [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									107,964,000	123,603,000
Marlin Gas Services [Member] | Unregulated Energy | Energy Services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									5,702,000	121,000
Eliminations [Member] | Regulated Energy
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									(38,934,000)	(33,754,000)
Eliminations [Member] | Unregulated Energy
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax									$ (8,758,000)	$ (14,529,000)

Revenue Recognition Remaining p

Revenue Recognition Remaining performance obligations (Details) $ in Thousands	Dec. 31, 2019USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01 | Eastern Shore and Peninsula Pipeline [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 37,307
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01 | Natural gas distribution operations [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	3,996
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01 | FPU Electric Distribution [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	566
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01 | Total for Segments [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	41,869
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01 | Eastern Shore and Peninsula Pipeline [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	34,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01 | Natural gas distribution operations [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	4,058
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01 | FPU Electric Distribution [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	566
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01 | Total for Segments [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	38,624
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01 | Eastern Shore and Peninsula Pipeline [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	27,034
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01 | Natural gas distribution operations [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	5,100
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01 | FPU Electric Distribution [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	566
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01 | Total for Segments [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	32,700
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01 | Eastern Shore and Peninsula Pipeline [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	21,608
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01 | Natural gas distribution operations [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	4,916
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01 | FPU Electric Distribution [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	566
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01 | Total for Segments [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	27,090
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01 | Eastern Shore and Peninsula Pipeline [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	19,385
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01 | Natural gas distribution operations [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	4,681
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01 | FPU Electric Distribution [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	566
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01 | Total for Segments [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	24,632
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 | Eastern Shore and Peninsula Pipeline [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	194,868
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 | Natural gas distribution operations [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	37,149
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 | FPU Electric Distribution [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	1,100
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 | Total for Segments [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 233,117

Segment Information - Schedule

Segment Information - Schedule of Segment Reporting Information by Segment (Detail) - USD ($) $ in Thousands		3 Months Ended									12 Months Ended
		Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018		Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018		Dec. 31, 2017
Operating Revenues, Unaffiliated Customers
Total intersegment revenues		$ 131,973	$ 92,626	$ 94,541	$ 160,464	$ 134,214		$ 93,400	$ 93,872	$ 168,831	$ 479,604	$ 490,316		$ 449,646
Intersegment Revenues (1)
Total intersegment revenues		131,973	92,626	94,541	160,464	134,214		93,400	93,872	168,831	479,604	490,316		449,646
Operating Income
Operating Income		29,642	14,358	18,164	44,123	28,873		12,879	12,238	40,853	106,287	94,843		89,730
Other income											(1,830)	(603)		(2,204)
Interest charges											22,224	16,146		12,530
Income Before Income taxes											82,233	78,094		74,996
Income Taxes on Continuing Operations											21,091	21,232		14,670
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent		17,169	6,246	8,913	28,814	17,796		6,090	5,705	27,271	61,142	56,862		60,326
Net Income		22,562	5,622	8,304	28,665	17,801		5,538	6,385	26,856	65,153	56,580		58,124
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent		(9)	(624)	(609)	(149)	5		$ (552)	$ 680	$ (415)	(1,391)	(282)		(2,202)
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax		5,402	$ 0	$ 0	$ 0						5,402
Depreciation and Amortization
Total depreciation and amortization											45,423	40,220		36,386
Identifiable Assets
Total identifiable assets		1,783,198				1,693,671					1,783,198	1,693,671
Regulated Energy
Operating Income
Operating Income											86,584	79,215		74,584
Depreciation and Amortization
Total depreciation and amortization											35,227	31,876		28,554
Payments to Acquire Productive Assets											130,604	235,912		159,011
Identifiable Assets
Total identifiable assets		1,434,066				1,345,805					1,434,066	1,345,805
Unregulated Energy
Operating Income
Operating Income											19,939	17,124		14,941
Depreciation and Amortization
Total depreciation and amortization											10,129	8,263		7,741
Payments to Acquire Productive Assets											60,034	38,585		14,424
Identifiable Assets
Total identifiable assets		296,810				245,702	[1]				296,810	245,702	[1]
Other
Operating Income
Operating Income											(236)	(1,496)		205
Depreciation and Amortization
Payments to Acquire Productive Assets											8,348	8,364		5,902
Identifiable Assets
Total identifiable assets		$ 52,322				41,821					52,322	41,821
Other and eliminations
Depreciation and Amortization
Total depreciation and amortization											67	81		91
Total for Segments [Member]
Depreciation and Amortization
Payments to Acquire Productive Assets											198,986	282,861		179,337
Continuing Operations [Member]
Identifiable Assets
Total identifiable assets	[1]					$ 1,633,328						1,633,328
Operating Segments
Operating Revenues, Unaffiliated Customers
Total intersegment revenues											479,604	490,316		449,646
Intersegment Revenues (1)
Total intersegment revenues											479,604	490,316		449,646
Operating Segments | Regulated Energy
Operating Revenues, Unaffiliated Customers
Total intersegment revenues											340,857	343,313		323,972
Intersegment Revenues (1)
Total intersegment revenues											340,857	343,313		323,972
Operating Segments | Unregulated Energy
Operating Revenues, Unaffiliated Customers
Total intersegment revenues											138,747	147,003		125,674
Intersegment Revenues (1)
Total intersegment revenues											138,747	147,003		125,674
Intersegment Eliminations
Operating Revenues, Unaffiliated Customers
Total intersegment revenues	[2]										18,080	17,522		17,514
Intersegment Revenues (1)
Total intersegment revenues	[2]										18,080	17,522		17,514
Intersegment Eliminations | Regulated Energy
Operating Revenues, Unaffiliated Customers
Total intersegment revenues	[2]										2,149	1,968		2,338
Intersegment Revenues (1)
Total intersegment revenues	[2]										2,149	1,968		2,338
Intersegment Eliminations | Unregulated Energy
Operating Revenues, Unaffiliated Customers
Total intersegment revenues	[2]										15,403	14,902		14,402
Intersegment Revenues (1)
Total intersegment revenues	[2]										15,403	14,902		14,402
Intersegment Eliminations | Other
Operating Revenues, Unaffiliated Customers
Total intersegment revenues	[2]										528	652		774
Intersegment Revenues (1)
Total intersegment revenues	[2]										$ 528	$ 652		$ 774
[1]	(1) 2018 balance excludes assets held for sale related to the sale of assets and contracts for PESCO.
[2]	All significant intersegment revenues are billed at market rates and have been eliminated from consolidated revenues.

Supplemental Cash Flow Disclo_3

Supplemental Cash Flow Disclosures - Cash Paid for Interest and Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Supplemental Cash Flow Disclosures Cash Paid For Interest And Income Taxes [Abstract]
Cash paid for interest	$ 22,611	$ 16,741	$ 12,420
Cash paid for income taxes	$ 3,221	$ 477	$ (4,114)

Supplemental Cash Flow Disclo_4

Supplemental Cash Flow Disclosures - Non-Cash Investing and Financing Activities (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Supplemental Cash Flow Disclosures Noncash Investing And Financing Activities [Abstract]
Capital property and equipment acquired on account, but not paid as of December 31	$ 13,470	$ 39,402	$ 15,457
Performance Incentive Plan	1,691	2,006	1,127
Capital Lease Obligation	$ 0	$ 1,310	$ 2,070

Derivative Instruments - Additi

Derivative Instruments - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Energy Marketing Contract Liabilities, Current	$ 1,844	$ 1,604
Derivative assets, at fair value	0	82
Unrealized Gain (Loss) on Derivatives	910	(2,701)	$ 1,715
Derivatives designated as fair value hedges | Mark To Market Energy Assets | Put Option
Derivative [Line Items]
Derivative assets, at fair value	0	71
Derivatives designated as fair value hedges | Mark To Market Energy Assets | Propane Swap Agreement
Derivative [Line Items]
Derivative assets, at fair value	0	11
Sharp Energy Inc [Member]
Derivative [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	(1,500)
Other Receivables from Broker-Dealers and Clearing Organizations	2,317	2,173
2017 [Member] | Derivatives designated as fair value hedges | Mark-to-market energy liabilities | Propane Swap Agreement
Derivative [Line Items]
Energy Marketing Contract Liabilities, Current	1,844	1,604
Other Comprehensive Income (Loss) | Derivatives designated as fair value hedges | Natural Gas Futures [Member]
Derivative [Line Items]
Unrealized Gain (Loss) on Derivatives	(294)	532	(1,476)
Other Comprehensive Income (Loss) | Derivatives designated as fair value hedges | Natural Gas Swaps [Member]
Derivative [Line Items]
Unrealized Gain (Loss) on Derivatives	(63)	200	986
Other Comprehensive Income (Loss) | Derivatives designated as fair value hedges | Propane Swap Agreement
Derivative [Line Items]
Unrealized Gain (Loss) on Derivatives	(253)	(2,773)	487
Cost of Sales [Member] | Not Designated as Hedging Instrument [Member] | Propane Swap Agreement
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net	0	(13)	8
Cost of Sales [Member] | Derivatives designated as fair value hedges | Propane Swap Agreement
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 1,520	$ (647)	$ 1,607

Derivative Instruments - Fair V

Derivative Instruments - Fair Values of Derivative Contracts Recorded in Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Energy Marketing Contracts Assets, Current	$ 0	$ 82
Energy Marketing Contract Liabilities, Current	1,844	1,604
Designated as Hedging Instrument [Member] | Mark To Market Energy Assets | Propane Swap Agreement
Derivatives, Fair Value [Line Items]
Energy Marketing Contracts Assets, Current	0	11
Designated as Hedging Instrument [Member] | Mark To Market Energy Assets | Put Option
Derivatives, Fair Value [Line Items]
Energy Marketing Contracts Assets, Current	0	71
2017 [Member] | Designated as Hedging Instrument [Member] | Mark-to-market energy liabilities | Propane Swap Agreement
Derivatives, Fair Value [Line Items]
Energy Marketing Contract Liabilities, Current	$ 1,844	$ 1,604

Derivative Instruments - Effect

Derivative Instruments - Effects of Gains and Losses from Derivative Instruments (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Energy Marketing Contract Liabilities, Current		$ 1,844	$ 1,604
Gain (Loss) on derivatives		910	(2,701)	$ 1,715
Revenue | Derivatives not designated as hedging instruments | Forward Contracts
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	[1]	0	0	112
Cost of Sales | Derivatives not designated as hedging instruments | Propane Swap Agreement
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net		0	(13)	8
Cost of Sales | Derivatives designated as fair value hedges | Put Or Call Option [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net		0	0	(9)
Cost of Sales | Derivatives designated as fair value hedges | Propane Swap Agreement
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net		1,520	(647)	1,607
Other Comprehensive Income (Loss) | Derivatives designated as fair value hedges | Natural Gas Futures [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on derivatives		(294)	532	(1,476)
Other Comprehensive Income (Loss) | Derivatives designated as fair value hedges | Propane Swap Agreement
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on derivatives		(253)	(2,773)	487
Other Comprehensive Income (Loss) | Derivatives designated as fair value hedges | Natural Gas Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on derivatives		(63)	200	$ 986
2017 [Member] | Mark To Market Energy Liabilities [Member] | Derivatives designated as fair value hedges | Propane Swap Agreement
Derivative Instruments, Gain (Loss) [Line Items]
Energy Marketing Contract Liabilities, Current		$ 1,844	$ 1,604
[1]	All of the realized and unrealized gain (loss) on forward contracts represented the effect of trading activities for Xeron on our consolidated statement of income.

Derivative Instruments Volume o

Derivative Instruments Volume of Derivative Activity (Details)	12 Months Ended
	Dec. 31, 2019gal
Sharp Energy Inc [Member] | Swap [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume	9,900,000

Fair Value of Financial Instr_3

Fair Value of Financial Instruments - Additional Information (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Disclosure Fair Value Of Financial Instruments Additional Information [Abstract]
Long-term debt including current maturities	$ 486.6	$ 327.2
Fair value of long-term debt	$ 505	$ 323.8

Fair Value of Financial Instr_4

Fair Value of Financial Instruments - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Assets:
Investments	$ 9,229	$ 6,711
Fair Value, Inputs, Level 1 [Member]
Assets:
Assets, Fair Value Disclosure	8,426	6,025
Fair Value, Inputs, Level 1 [Member] | Mark-to-market energy liabilities
Liabilities:
Mark-to-market energy liabilities	0
Significant Other Observable Inputs (Level 2)
Assets:
Assets, Fair Value Disclosure	0	82
Significant Other Observable Inputs (Level 2) | Mark-to-market energy liabilities
Liabilities:
Mark-to-market energy liabilities	1,844	1,604	[1]
Significant Unobservable Inputs (Level 3)
Assets:
Assets, Fair Value Disclosure	803	686
Significant Unobservable Inputs (Level 3) | Mark-to-market energy liabilities
Liabilities:
Mark-to-market energy liabilities	0
Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Assets:
Investments	27	22
Equity Securities [Member] | Significant Other Observable Inputs (Level 2)
Assets:
Investments	0
Equity Securities [Member] | Significant Unobservable Inputs (Level 3)
Assets:
Investments	0
Guaranteed Income Fund [Member] | Fair Value, Inputs, Level 1 [Member]
Assets:
Investments	0
Guaranteed Income Fund [Member] | Significant Other Observable Inputs (Level 2)
Assets:
Investments	0
Guaranteed Income Fund [Member] | Significant Unobservable Inputs (Level 3)
Assets:
Investments	803	686
Other Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Assets:
Investments	8,399	6,003
Other Investments [Member] | Significant Other Observable Inputs (Level 2)
Assets:
Investments	0
Other Investments [Member] | Significant Unobservable Inputs (Level 3)
Assets:
Investments	0
Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Assets:
Investments	8,426	6,025
Investments [Member] | Significant Other Observable Inputs (Level 2)
Assets:
Investments	0	0
Investments [Member] | Significant Unobservable Inputs (Level 3)
Assets:
Investments	803	686
Mark-to-market energy assets, including put option | Fair Value, Inputs, Level 1 [Member]
Assets:
Mark-to-market energy assets, including put option	0
Mark-to-market energy assets, including put option | Significant Other Observable Inputs (Level 2)
Assets:
Mark-to-market energy assets, including put option	0	82	[1]
Mark-to-market energy assets, including put option | Significant Unobservable Inputs (Level 3)
Assets:
Mark-to-market energy assets, including put option	0
Fair Value
Assets:
Assets, Fair Value Disclosure	9,229	6,793
Fair Value | Mark-to-market energy liabilities
Liabilities:
Mark-to-market energy liabilities	1,844	1,604	[1]
Fair Value | Equity Securities [Member]
Assets:
Investments	27	22
Fair Value | Guaranteed Income Fund [Member]
Assets:
Investments	803	686
Fair Value | Other Investments [Member]
Assets:
Investments	8,399	6,003
Fair Value | Investments [Member]
Assets:
Investments	9,229	6,711
Fair Value | Mark-to-market energy assets, including put option
Assets:
Mark-to-market energy assets, including put option	$ 0	$ 82	[1]
[1]	(1) As discussed in Note 4, Acquisitions and Divestitures

Fair Value of Financial Instr_5

Fair Value of Financial Instruments Fair Value of Financial Instruments - Summary of Changes in Fair Value of Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	$ (29)	$ (41)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	686	648
Purchases and adjustments	131	68
Investment income	15	11
Ending Balance	$ 803	$ 686

Investments - Additional Inform

Investments - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Investments [Abstract]
Unrealized gain, net of other expenses	$ 1,600	$ (400)	$ 1,000

Investments - Schedule of Inves

Investments - Schedule of Investment (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Investment [Line Items]
Investments, at fair value	$ 9,229	$ 6,711
Fair Value, Inputs, Level 1 [Member] | Investments in equity securities
Investment [Line Items]
Investments, at fair value	$ 27	$ 22

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($)		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018
Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross		$ 12,365,000	$ 7,316,000
Acquired finite-lived intangible assets, weighted average useful life		11 years
Goodwill		$ 32,668,000	21,568,000
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months		800,000
Amortization of intangible assets		400,000
Finite-Lived Intangible Assets, Amortization Expense, Year Four		900,000
Amortization of intangible assets, 2019		1,200,000
Amortization of intangible assets, 2020		1,153,466
Amortization of intangible assets, 2022		800,000
Customer list
Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross		$ 9,391,000	4,801,000
Customer list | Minimum
Goodwill [Line Items]
Amortized period of acquired intangible assets		5 years
Customer list | Boulden [Member]
Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross		$ 4,600,000
Noncompete Agreements [Member]
Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross		2,252,000	$ 1,793,000
Noncompete Agreements [Member] | Boulden [Member]
Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross		500,000
Boulden [Member] | Unregulated Energy
Goodwill [Line Items]
Goodwill	[1]	$ 11,200,000
[1]	(3) Mid-Atlantic Propane Operations goodwill balance includes $11.2 million recognized as a result of the purchase of the operating assets of Boulden in December 2019.

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets - Schedule of Carrying Value of Goodwill (Detail) - USD ($) $ in Thousands		Dec. 31, 2019		Dec. 31, 2018
Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross		$ 12,365		$ 7,316
Finite-Lived Intangible Assets, Accumulated Amortization		4,236		3,466
Goodwill		32,668		21,568
Boulden [Member] | Unregulated Energy
Goodwill [Line Items]
Goodwill	[1]	11,200
Florida Natural Gas Distribution [Member] | Regulated Energy
Goodwill [Line Items]
Goodwill	[2]	3,353		3,353
Mid-Atlantic Propane Operations [Member] | Unregulated Energy
Goodwill [Line Items]
Goodwill		13,299	[1]	2,147
Florida Propane Operations [Member] | Unregulated Energy
Goodwill [Line Items]
Goodwill		1,188		1,188
Aspire Energy | Unregulated Energy
Goodwill [Line Items]
Goodwill		10,120		10,120
Marlin Gas Services [Member] | Unregulated Energy
Goodwill [Line Items]
Goodwill		4,708		4,760
Customer Lists [Member]
Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross		9,391		4,801
Finite-Lived Intangible Assets, Accumulated Amortization		3,463		3,066
Noncompete Agreements [Member]
Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross		2,252		1,793
Finite-Lived Intangible Assets, Accumulated Amortization		451		202
Patents [Member]
Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross		452		452
Finite-Lived Intangible Assets, Accumulated Amortization		118		0
Other Intangible Assets [Member]
Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross		270		270
Finite-Lived Intangible Assets, Accumulated Amortization		$ 204		$ 198
[1]	(3) Mid-Atlantic Propane Operations goodwill balance includes $11.2 million recognized as a result of the purchase of the operating assets of Boulden in December 2019.
[2]	(1) Florida Natural Gas Distribution includes Chesapeake Utilities' Central Florida Gas division, FPU and FPU's Indiantown and Fort Meade divisions.

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets - Schedule of Carrying Value and Accumulated Amortization of Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 12,365	$ 7,316
Accumulated Amortization	4,236	3,466
Customer Lists [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	9,391	4,801
Accumulated Amortization	3,463	3,066
Noncompete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,252	1,793
Accumulated Amortization	451	202
Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	452	452
Accumulated Amortization	118	0
Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	270	270
Accumulated Amortization	$ 204	$ 198

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Loss Carryforwards [Line Items]
Federal net operating losses for income tax	$ (3,000)	$ (12,200)
Deferred Tax Assets, Operating Loss Carryforwards	$ 5,523	2,010
Deferred tax asset related to state net operating loss carry-forwards		$ 2,000
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	35.00%
State
Operating Loss Carryforwards [Line Items]
Federal net operating losses for income tax	$ 54,700	$ 60,100

Income Taxes - Schedule of Inco

Income Taxes - Schedule of Income Tax Expense (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current Income Tax Expense
Federal		$ (2,271)	$ 48	$ 2,046
State		(492)	581	610
Other		(47)	(47)	(71)
Total current income tax expense (benefit)		(2,810)	582	2,585
Deferred Income Tax Expense (1)
Total deferred income tax expense	[1]	23,901	20,650	12,085
Income Tax Expense from Continuing Operations		21,091	21,232	14,670
Discontinued Operation, Tax Effect of Gain (Loss) from Disposal of Discontinued Operation		(1,439)	(238)	(361)
Income Tax Expense (Benefit), Continuing Operations, Discontinued Operations		22,530	20,994	14,309
Property, plant and equipment
Deferred Income Tax Expense (1)
Total deferred income tax expense		25,910	19,189	8,181
Deferred gas costs
Deferred Income Tax Expense (1)
Total deferred income tax expense		79	(1,435)	2,002
Pensions and other employee benefits
Deferred Income Tax Expense (1)
Total deferred income tax expense		(454)	446	180
FPU merger related premium cost and deferred gain
Deferred Income Tax Expense (1)
Total deferred income tax expense		(278)	(528)	(1,148)
Net operating loss carryforwards
Deferred Income Tax Expense (1)
Total deferred income tax expense		(3,776)	(183)	193
Other
Deferred Income Tax Expense (1)
Total deferred income tax expense		$ 2,420	$ 3,161	$ 2,677
[1]	(1) Includes $4.7 million , $3.5 million , and $0.9 million of deferred state income taxes for the years 2019 , 2018 and 2017 , respectively.

Income Taxes - Summary of Recon

Income Taxes - Summary of Reconciliation of Statutory Federal Tax and Effective Income Tax Rates (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Income Taxes Summary Of Reconciliation Of Statutory Federal Tax And Effective Income Tax Rates [Abstract]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent		21.00%	21.00%	35.00%
Reconciliation of Effective Income Tax Rates Continuing Operations
Federal income tax expense (1)	[1]	$ 17,246	$ 16,491	$ 26,249
State income taxes, net of federal benefit		5,088	4,057	2,000
ESOP dividend deduction		(173)	(158)	(257)
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount		0		(14,299)
Other		(1,070)	842	977
Income Tax Expense from Continuing Operations		$ 21,091	$ 21,232	$ 14,670
Effective Income Tax Rate for Continuing Operations (2)	[2]	25.65%	27.19%	19.56%
[1]	Federal income taxes were calculated at 21 percent for 2019 and 2018 and 35 percent for 2017.
[2]	The effective tax rate for 2017 includes the impact of the revaluation of deferred tax assets and liabilities for our unregulated businesses due to implementation of the TCJA

Income Taxes - Schedule of Accu

Income Taxes - Schedule of Accumulated Deferred Income Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Income Taxes Schedule Of Accumulated Deferred Income Tax Assets And Liabilities [Abstract]
Deferred State and Local Income Tax Expense (Benefit)	$ 4,700	$ 3,500	$ 900
Deferred income tax liabilities:
Property, plant and equipment	173,466	153,423
Acquisition adjustment	6,969	8,896
Deferred Tax Liabilities Loss On Reacquired Debt	220	32
Deferred Income Tax Liability - Deferred Gas Costs	1,223	1,139
Deferred Income Tax Liability, Natural Gas Conversion Costs	4,956	3,987
Deferred Income Tax Liability, Storm Reserve	10,316	97
Other	1,456	2,544
Total deferred income tax liabilities	198,606	170,118
Deferred income tax assets:
Pension and other employee benefits	3,818	3,711
Environmental costs	1,486	1,710
Net operating loss carryforwards	5,523	2,010
Self-insurance	146	151
Storm reserve liability	96	0
Other	6,881	5,716
Total deferred income tax assets	17,950	13,298
Deferred Income Tax Liabilities, Net	$ 180,656	$ 156,820

Income Taxes - Schedule of In_2

Income Taxes - Schedule of Income Tax Expense (Phantoms) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Income Taxes Schedule Of Income Tax Expense [Abstract]
Deferred state income taxes	$ 4,700	$ 3,500	$ 900

Income Taxes - Summary of Rec_2

Income Taxes - Summary of Reconciliation of Statutory Federal Tax and Effective Income Tax Rates (Phantoms) (Detail)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Income Taxes Summary Of Reconciliation Of Statutory Federal Tax And Effective Income Tax Rates [Abstract]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	35.00%

Income Taxes Federal Tax Reform

Income Taxes Federal Tax Reform (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Federal Tax Reform
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	35.00%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	$ 0		$ (14,299)

Long-Term Debt - Additional Inf

Long-Term Debt - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term debt maturities repayment of principal in next twelve months	$ 45,600,000
Long-term debt maturities repayment of principal in year two	13,600,000
Long-term debt maturities repayment of principal in year three	25,100,000
Long-term debt maturities repayment of principal in year four	20,600,000
Long-term debt maturities repayment of principal in year five	17,600,000
Long-term debt maturities repayment of principal in year five thereafter	364,100,000
Debt Instrument, Unused Borrowing Capacity, Amount	$ 250,000,000
Percentage of equity of total capitalization	40.00%
Fixed charge coverage ratio	1.2
Required net book value of regulated business assets, minimum percentage of consolidated total assets	50.00%
Maximum limit on payment of dividends	$ 10,000,000
Cumulative consolidated net income base	509,500,000
Cumulative net income with restrictions	227,500,000
Cumulative net income free of restrictions	282,000,000
Restricted net assets of consolidated subsidiaries	$ 38,800,000
Percentage of restricted net assets	6.92%
Long-term debt including current maturities	$ 486,600,000	$ 327,200,000
Term Note Due January Two Thousand Twenty [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	3.23%
Long-term debt including current maturities	$ 0	30,000,000
Uncollateralized Senior Note Due On Two Thousand Twenty Six [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	5.68%
Long-term debt including current maturities	$ 20,300,000	23,200,000
First Mortgage Bond Due On Two Thousand Twenty Two [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	9.08%
Cumulative consolidated net income base	$ 168,100,000
Cumulative net income with restrictions	(37,600,000)
Cumulative net income free of restrictions	130,500,000
Long-term debt including current maturities	$ 7,990,000	7,986,000
Uncollateralized Senior Note Due December Two Thousand Thirty Four [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	2.98%
Long-term debt including current maturities	$ 70,000,000
Uncollateralized Senior Note Due On May 2 Two Thousand Twenty Eight [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	6.43%
Long-term debt including current maturities	$ 6,300,000	7,000,000
Uncollateralized Senior Note Two Due on December Two Thousand Twenty Eight [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	3.73%
Long-term debt including current maturities	$ 18,000,000	20,000,000
Uncollateralized Senior Notes Due On Two Thousand Twenty Nine [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	3.88%
Long-term debt including current maturities	$ 50,000,000	50,000,000
Uncollateralized Senior Note One Due On Two Thousand Seventeen [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	6.64%
Uncollateralized Senior Note Due On Two Thousand Twenty [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	5.50%
Long-term debt including current maturities	$ 2,000,000	4,000,000
Uncollateralized Senior Note Due On Two Thousand Twenty Three [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	5.93%
Long-term debt including current maturities	$ 12,000,000	$ 15,000,000
Florida Public Utilities Company [Member]
Debt Instrument [Line Items]
Cumulative net income with restrictions	$ 2,500,000

Long-Term Debt - Outstanding Lo

Long-Term Debt - Outstanding Long-Term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Restricted Payment	$ 227,500
Long-term Debt	486,600	$ 327,200
Capital lease obligation	0	1,310
Less: debt issuance costs	(822)	(567)
Long-term Debt and Lease Obligation	485,768	327,955
Less: current maturities	(45,600)	(11,935)
Total long-term debt, net of current maturities	440,168	316,020
Unrestricted Payment	282,000
9.08% bond, due June 1, 2022
Debt Instrument [Line Items]
Restricted Payment	(37,600)
Long-term Debt	$ 7,990	7,986
Debt Instrument, Interest Rate, Stated Percentage	9.08%
Unrestricted Payment	$ 130,500
6.64% note, due October 31, 2017
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.64%
5.50% note, due October 12, 2020
Debt Instrument [Line Items]
Long-term Debt	$ 2,000	4,000
Debt Instrument, Interest Rate, Stated Percentage	5.50%
5.93% note, due October 31, 2023
Debt Instrument [Line Items]
Long-term Debt	$ 12,000	15,000
Debt Instrument, Interest Rate, Stated Percentage	5.93%
5.68% note, due June 30, 2026
Debt Instrument [Line Items]
Long-term Debt	$ 20,300	23,200
Debt Instrument, Interest Rate, Stated Percentage	5.68%
6.43% note, due May 2, 2028
Debt Instrument [Line Items]
Long-term Debt	$ 6,300	7,000
Debt Instrument, Interest Rate, Stated Percentage	6.43%
3.73% note, due December 16, 2028
Debt Instrument [Line Items]
Long-term Debt	$ 18,000	20,000
Debt Instrument, Interest Rate, Stated Percentage	3.73%
3.88% note, due May 15, 2029
Debt Instrument [Line Items]
Long-term Debt	$ 50,000	50,000
Debt Instrument, Interest Rate, Stated Percentage	3.88%
Uncollateralized Senior Note Due April Two Thousand Thirty Two [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 70,000	70,000
Uncollateralized Senior Note Due May Two Thousand Thirty Eight [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 50,000	50,000
Debt Instrument, Interest Rate, Stated Percentage	3.48%
Uncollateralized Senior Note Due November Two Thousand Thirty Eight [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 50,000	50,000
Debt Instrument, Interest Rate, Stated Percentage	3.58%
Uncollateralized Senior Note Due August Two Thousand Thirty Nine [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 100,000
Debt Instrument, Interest Rate, Stated Percentage	3.98%
Uncollateralized Senior Note Due December Two Thousand Thirty Four [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 70,000
Debt Instrument, Interest Rate, Stated Percentage	2.98%
Term Note Due January Two Thousand Twenty [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 0	30,000
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	0.75%
Debt Instrument, Interest Rate, Stated Percentage	3.23%
Term Note Due February Two Thousand Twenty [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 30,000
Debt Instrument, Interest Rate, Stated Percentage	2.46%
Promissory note
Debt Instrument [Line Items]
Long-term Debt	$ 0	$ 26
Electric Limited Proceedings [Member]
Debt Instrument [Line Items]
Basis Plus LIBOR for Term Notes to Finance Hurricane Michael Costs	75

Long-Term Debt - Outstanding _2

Long-Term Debt - Outstanding Long-Term Debt (Phantoms) (Detail)	12 Months Ended
	Dec. 31, 2019
9.08% bond, due June 1, 2022
Debt Instrument [Line Items]
Long-term debt, interest percentage	9.08%
Debt Instrument, Maturity Date	Jun. 1, 2022
6.64% note, due October 31, 2017
Debt Instrument [Line Items]
Long-term debt, interest percentage	6.64%
Debt Instrument, Maturity Date	Oct. 31, 2017
5.50% note, due October 12, 2020
Debt Instrument [Line Items]
Long-term debt, interest percentage	5.50%
Debt Instrument, Maturity Date	Oct. 12, 2020
5.93% note, due October 31, 2023
Debt Instrument [Line Items]
Long-term debt, interest percentage	5.93%
Debt Instrument, Maturity Date	Oct. 31, 2023
5.68% note, due June 30, 2026
Debt Instrument [Line Items]
Long-term debt, interest percentage	5.68%
Debt Instrument, Maturity Date	Jun. 30, 2026
6.43% note, due May 2, 2028
Debt Instrument [Line Items]
Long-term debt, interest percentage	6.43%
Debt Instrument, Maturity Date	May 2, 2028
3.73% note, due December 16, 2028
Debt Instrument [Line Items]
Long-term debt, interest percentage	3.73%
Debt Instrument, Maturity Date	Dec. 16, 2028
3.88% note, due May 15, 2029
Debt Instrument [Line Items]
Long-term debt, interest percentage	3.88%
Debt Instrument, Maturity Date	May 15, 2029
Uncollateralized Senior Note Due on Two Thousand Thirty Two [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	3.25%
Debt Instrument, Maturity Date	Apr. 30, 2032
Uncollateralized Senior Note Due May Two Thousand Thirty Eight [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	3.48%
Debt Instrument, Maturity Date	May 31, 2038
Uncollateralized Senior Note Due November Two Thousand Thirty Eight [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	3.58%
Debt Instrument, Maturity Date	Nov. 30, 2038
Uncollateralized Senior Note Due August Two Thousand Thirty Nine [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	3.98%
Debt Instrument, Maturity Date	Aug. 20, 2039
Uncollateralized Senior Note Due December Two Thousand Thirty Four [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	2.98%
Debt Instrument, Maturity Date	Dec. 20, 2034
Term Note Due January Two Thousand Twenty [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	3.23%
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	0.75%
Debt Instrument, Maturity Date	Jan. 21, 2020
Term Note Due February Two Thousand Twenty [Member]
Debt Instrument [Line Items]
Long-term debt, interest percentage	2.46%
Debt Instrument, Maturity Date	Feb. 28, 2020

Long-Term Debt Annual Maturitie

Long-Term Debt Annual Maturities (Details) $ in Thousands	Dec. 31, 2019USD ($)
Long Term Debt Annual Maturities [Abstract]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	$ 45,600
Long-term Debt, Maturities, Repayments of Principal in Year Two	13,600
Long-term Debt, Maturities, Repayments of Principal in Year Three	25,100
Long-term Debt, Maturities, Repayments of Principal in Year Four	20,600
Long-term Debt, Maturities, Repayments of Principal in Year Five	17,600
Long-term Debt, Maturities, Repayments of Principal after Year Five	364,100
Total Future Repayments	$ 486,600

Long-Term Debt Shelf Arrangemen

Long-Term Debt Shelf Arrangements (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Line of Credit Facility [Line Items]
Long-term Debt	$ (486,600)	$ (327,200)
Debt Instrument, Unused Borrowing Capacity, Amount	250,000
Prudential [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Face Amount	150,000
Long-term Debt	(170,000)
Debt Instrument, Unused Borrowing Capacity, Amount	50,000
MetLife [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Unused Borrowing Capacity, Amount	150,000
New York Life [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Face Amount	100,000
Long-term Debt	(100,000)
Debt Instrument, Unused Borrowing Capacity, Amount	50,000
Aggregate Shelf Agreements [Member]
Line of Credit Facility [Line Items]
Long-term Debt	(270,000)
Unsecured Debt [Member]
Line of Credit Facility [Line Items]
Long-term Debt	$ (50,000)
Debt Instrument, Interest Rate, Stated Percentage	3.00%
Aggregated Unfunded Commitments [Member]
Line of Credit Facility [Line Items]
Long-term Debt	$ 0
Uncollateralized Senior Note to be Issued in 2019 [Member]
Line of Credit Facility [Line Items]
Long-term Debt	$ 0
Debt Instrument, Interest Rate, Stated Percentage	3.98%
Uncollateralized Senior Note Due April Two Thousand Thirty Two [Member]
Line of Credit Facility [Line Items]
Long-term Debt	$ (70,000)	$ (70,000)
NYL Unsecured Debt [Member]
Line of Credit Facility [Line Items]
Long-term Debt	$ (40,000)
Debt Instrument, Interest Rate, Stated Percentage	2.96%
Uncollateralized Senior Note Due on Two Thousand Thirty Two [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.25%
Uncollateralized Senior Note Due August Two Thousand Thirty Nine [Member]
Line of Credit Facility [Line Items]
Long-term Debt	$ (100,000)
Debt Instrument, Interest Rate, Stated Percentage	3.98%
Maximum [Member] | Prudential [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Face Amount	$ 220,000
Maximum [Member] | MetLife [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Face Amount	150,000
Maximum [Member] | New York Life [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Face Amount	150,000
Maximum [Member] | Aggregate Shelf Agreements [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Face Amount	$ 520,000

Short-Term Borrowing - Addition

Short-Term Borrowing - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Oct. 08, 2015USD ($)
Short-term Debt [Line Items]
Short-term borrowings	$ 247,371,000	$ 294,458,000
Line of Credit Facility, Aggregate Borrowing Capacity	$ 370,000,000
Number Of Unsecured Bank Credit Facilities	4
Number Of Financial Institutions With Bank Credit Facilities	4
Line Of Available Credit Facility Borrowing Capacity	$ 220,000,000
ParticipatingLendersInTheRevolver	5
Short-term Debt, Weighted Average Interest Rate, at Point in Time	2.62%	3.44%
Line of Credit Facility, Commitment Fee Amount	$ 100,000
Ratio of Indebtedness to Net Capital	0.65
Uncommitted Line Of Credit Facility One [Member]
Short-term Debt [Line Items]
Line of Credit Facility, Current Borrowing Capacity			$ 150,000,000
Revolving Credit Facility [Member]
Short-term Debt [Line Items]
Line of Credit Facility, Aggregate Borrowing Capacity	$ 370,000,000
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
Line of Credit Facility, Aggregate Borrowing Capacity	$ 80,000,000
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
Line of Credit Facility, Aggregate Borrowing Capacity	$ 45,000,000

Short-Term Borrowing Short-Te_2

Short-Term Borrowing Short-Term Borrowing - Schedule of Short-Term Debt (Details) $ in Thousands		12 Months Ended
		Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Short-term Debt [Line Items]
Short-term Debt, Maximum Amount Outstanding During Period		$ 250,000
Line of Credit Facility, Maximum Borrowing Capacity		370,000
Long-term Line of Credit		244,190	$ 290,103
Line of Credit Facility, Remaining Borrowing Capacity		125,810
Bank Overdrafts	[1]	3,181	4,355
Short-term borrowing		$ 247,371	294,458
Number Of Unsecured Bank Credit Facilities		4
Committed Line of Credit Facility One [Member]
Short-term Debt [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 55,000
Long-term Line of Credit		55,000	25,000
Line of Credit Facility, Remaining Borrowing Capacity		$ 0
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]
Line of Credit Facility, Maximum Borrowing Capacity		$ 45,000
Long-term Line of Credit		42,040	34,672
Line of Credit Facility, Remaining Borrowing Capacity		$ 2,960
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]
Line of Credit Facility, Maximum Borrowing Capacity		$ 40,000
Long-term Line of Credit		40,000	40,000
Line of Credit Facility, Remaining Borrowing Capacity		$ 0
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]
Line of Credit Facility, Maximum Borrowing Capacity	[2]	$ 150,000
Long-term Line of Credit		50,000	125,000
Line of Credit Facility, Remaining Borrowing Capacity	[2]	$ 100,000
Debt Instrument, Description of Variable Rate Basis		LIBOR rate, plus 1.125 percent
Committed Line of Credit Facility Two [Member]
Short-term Debt [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 80,000
Long-term Line of Credit		57,150	$ 65,431
Line of Credit Facility, Remaining Borrowing Capacity		$ 22,850
Debt Instrument, Description of Variable Rate Basis		LIBOR rate, plus 0.75 percent
[1]	(1) If presented, these book overdrafts would be funded through the bank revolving credit facilities.
[2]	This committed revolving credit facility includes a restriction that our short-term borrowings, excluding any borrowings under the committed revolving credit facility, shall not exceed $250.0 million .

Leases Schedule of Future Minim

Leases Schedule of Future Minimum Rental Payment for Operating Leases (Details) $ in Thousands	Dec. 31, 2019USD ($)
Leases [Abstract]
Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months	$ 2,104
Lessee Future Operating Lease Option Payments	3,700
Lessee, Operating Lease, Liability, Payments, Due Year Two	1,866
Lessee, Operating Lease, Liability, Payments, Due Year Three	1,716
Lessee, Operating Lease, Liability, Payments, Due Year Four	1,719
Lessee, Operating Lease, Liability, Payments, Due Year Five	1,463
Lessee, Operating Lease, Liability, Payments, Due after Year Five	4,916
Lessee, Operating Lease, Liability, Payments, Due	13,784
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	2,183
Operating Lease, Liability	$ 11,601

Leases Lease Cost Additional (D

Leases Lease Cost Additional (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Leases [Abstract]
Operating Lease, Cost	$ 2,577	$ 3,339
Finance Lease, Right-of-Use Asset, Amortization	650	1,451
Finance Lease, Interest Expense	5	49
Lease, Cost	$ 3,232	$ 4,839

Leases Leases - Right of Use As

Leases Leases - Right of Use Asset and Lease Liability Balance Sheet Classification (Details) $ in Thousands	Dec. 31, 2019USD ($)
Leases [Abstract]
Operating Lease, Right-of-Use Asset	$ 11,563
Operating Lease, Liability, Current	1,705
Operating Lease, Liability, Noncurrent	9,896
Total Operating and Finance Lease Liabilities	$ 11,601

Leases Weighted Average Remaini

Leases Weighted Average Remaining Lease Term Additional Information (Details)	Dec. 31, 2019
Leases [Abstract]
Operating Lease, Weighted Average Remaining Lease Term	8 years 10 months 17 days
Operating Lease, Weighted Average Discount Rate, Percent	3.80%

Leases Lease Cash Flows Additio

Leases Lease Cash Flows Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Leases Cash Flows [Abstract]
Operating Lease, Payments	$ 2,230	$ 2,759
Finance Lease, Interest Expense	5	49
Finance Lease, Right-of-Use Asset, Amortization	$ 650	$ 1,451

Stockholders' Equity Additional

Stockholders' Equity Additional Details (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	[1]
Stockholders' Equity Attributable to Parent [Abstract]
Preferred Stock, Shares Authorized	2,000,000	2,000,000
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Proceeds from issuance of common stock, net of expenses	$ 0	$ 0	$ (10)
[1]	Represents capitalized legal fees associated with our September 22, 2016 public offering.

Stockholders' Equity Accumulate

Stockholders' Equity Accumulated Other comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), after Tax [Roll Forward]
Accumulated other comprehensive loss at beginning of period	$ (4,272)	$ (6,713)	$ (4,272)
Other Comprehensive Income (Loss), before Reclassifications, before Tax	(3,732)	1,289
Amounts reclassified from accumulated other comprehensive income/(loss)	2,198	(728)
Net current-period other comprehensive income/(loss)	(1,534)	561
Accumulated other comprehensive loss at end of period		(6,267)	(6,713)
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect	(907)
AOCI Changes For Defined Benefit Pension And Postretirement Plans [Member]
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), after Tax [Roll Forward]
Accumulated other comprehensive loss at beginning of period	(4,743)	(5,928)	(4,743)
Other Comprehensive Income (Loss), before Reclassifications, before Tax	(602)	(872)
Amounts reclassified from accumulated other comprehensive income/(loss)	439	1,867
Net current-period other comprehensive income/(loss)	(163)	995
Accumulated other comprehensive loss at end of period		(4,933)	(5,928)
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect	(1,022)
Accumulated (Gain) Loss from Commodity Contracts Cash Flows Hedges [Member]
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), after Tax [Roll Forward]
Accumulated other comprehensive loss at beginning of period	471	(785)	471
Other Comprehensive Income (Loss), before Reclassifications, before Tax	(3,130)	2,161
Amounts reclassified from accumulated other comprehensive income/(loss)	1,759	(2,595)
Net current-period other comprehensive income/(loss)	(1,371)	(434)
Accumulated other comprehensive loss at end of period		(1,334)	$ (785)
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect	$ 115	$ (115)

Stockholders' Equity Accumula_2

Stockholders' Equity Accumulated Other Comprehensive Income (loss) - Reclassifications of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Amortization of defined benefit pension and postretirement plan items:
Income tax benefit		$ (21,091)	$ (21,232)	$ (14,670)
Reclassification out of Accumulated Other Comprehensive Income [Member]
Amortization of defined benefit pension and postretirement plan items:
Net of tax		728	(2,198)	(166)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment [Member]
Amortization of defined benefit pension and postretirement plan items:
Prior service cost	[1]	77	77	77
Net gain	[1]	(2,600)	(579)	(636)
Total before income taxes		(2,523)	(502)	(559)
Income tax benefit	[2]	656	63	223
Net of tax		(1,867)	(439)	(336)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated (Gain) Loss from Commodity Contracts Cash Flows Hedges [Member]
Amortization of defined benefit pension and postretirement plan items:
Total before income taxes		3,623	(2,460)	329
Income tax benefit	[2]	(1,028)	701	(159)
Net of tax		2,595	(1,759)	170
Propane Swap Agreement [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated (Gain) Loss from Commodity Contracts Cash Flows Hedges [Member]
Amortization of defined benefit pension and postretirement plan items:
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	[3]	1,520	(647)	1,607
Natural Gas Futures [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated (Gain) Loss from Commodity Contracts Cash Flows Hedges [Member]
Amortization of defined benefit pension and postretirement plan items:
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	[3],[4]	2,096	(2,010)	(456)
Natural Gas Swaps [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated (Gain) Loss from Commodity Contracts Cash Flows Hedges [Member]
Amortization of defined benefit pension and postretirement plan items:
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	[3],[4]	$ 7	$ 197	$ (822)
[1]	These amounts are included in the computation of net periodic benefits. See Note 17 , Employee Benefit Plans , for additional details.
[2]	(4) The income tax benefit is included in income tax expense in the accompanying consolidated statements of income.
[3]	These amounts are included in the effects of gains and losses from derivative instruments. See Note 8, Derivative Instruments , for additional details.
[4]	(3) PESCO's results are reflected as discontinued operations in our consolidated statements of income.

Employee Benefit Plans - Additi

Employee Benefit Plans - Additional Information (Detail) $ in Thousands		12 Months Ended
		Dec. 31, 2019USD ($)planshares	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Number of Plans | plan		3
Income tax benefits		$ 1,700
Pre-merger regulatory asset		6
Total unrecognized cost		22,286
Expected Amortization Of Pre Merger Regulatory Asset		$ 0
Required period of service for eligibility		3 months
Percentage of eligible participants contribution to the plan		100.00%
Maximum percentage of eligible compensation		6.00%
Employer matching contribution vested, percentage		100.00%
Deferred Compensation Arrangement with Individual, Requisite Service Period		2 years
Deferred Pension Settlement Expense		$ (700)
Defined Benefit Plan, Benefit Obligation			2
Employee contribution age		55 years
Deferral rate		80.00%
Deferred Compensation Employer Matching Contribution Rate		6.00%
Number Of Years to Collect Benefits		20 years
Deferral rate increase, minimum		1.00%
Employer contributions to pension plan		$ 5,700	$ 5,500	$ 5,000
Shares reserved to fund future contributions | shares		831,183
Investments, Fair Value Disclosure		$ 9,229	6,711
Deferred compensation obligation		$ 4,543	$ 3,854
Minimum
Defined Benefit Plan Disclosure [Line Items]
Maximum percentage of eligible compensation		3.00%
Maximum
Defined Benefit Plan Disclosure [Line Items]
Maximum percentage of eligible compensation			10.00%
Number Of Years to Collect Benefits		15 years
Chesapeake Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Pre-merger regulatory asset		$ 0
Total unrecognized cost		2,241
Unfunded accumulated benefit obligation		(1,584)	$ (2,063)
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year		300
Expected contribution	[1]	115
FPU Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Pre-merger regulatory asset		0
Total unrecognized cost		19,339
Unfunded accumulated benefit obligation		(15,601)	(15,776)
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year		3,200
Expected contribution	[1]	3,281
Chesapeake SERP
Defined Benefit Plan Disclosure [Line Items]
Pre-merger regulatory asset		0
Total unrecognized cost		575
Unfunded accumulated benefit obligation		(2,157)	(2,285)
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year		200
Expected contribution	[2]	$ 151
Medical
Defined Benefit Plan Disclosure [Line Items]
Health care inflation rate		5.00%
Chesapeake Postretirement Plan
Defined Benefit Plan Disclosure [Line Items]
Pre-merger regulatory asset		$ 0
Total unrecognized cost		157
Unfunded accumulated benefit obligation		$ (1,100)	(1,002)
Expected Amortization Of Pre Merger Regulatory Asset			0	$ 0
Health care inflation rate		6.00%
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year		$ 100
Expected contribution	[2]	90
FPU Medical Plan
Defined Benefit Plan Disclosure [Line Items]
Pre-merger regulatory asset		6
Total unrecognized cost		(26)
Unfunded accumulated benefit obligation		$ (1,224)	(1,187)
Health care inflation rate		5.00%
Expected contribution	[2]	$ 86
Rabbi Trust Associated With Deferred Compensation [Member]
Defined Benefit Plan Disclosure [Line Items]
Investments, Fair Value Disclosure		$ 9,202	6,689
FPU Medical Plan and Chesapeake OPRB [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Number of Plans		2
Rabbi Trust Associated With Deferred Compensation Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Deferred compensation obligation		$ 9,200	6,700
Deferred Compensation Equity		$ 4,500	$ 3,900
[1]	The pension plan is funded; therefore, benefit payments are expected to be paid out of the plan assets.
[2]	Benefit payments are expected to be paid out of our general funds.

Employee Benefit Plans - Schedu

Employee Benefit Plans - Schedule of Funded Status of Benefit Obligation and Plan Assets (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Change in benefit obligation:
Interest cost		$ 74	$ 83	$ 89
Change in plan assets:
Balance, beginning of year		52,250
Balance, end of year		54,333	52,250
Chesapeake Pension Plan
Change in benefit obligation:
Benefit obligation - beginning of year		10,712	11,443
Interest cost		375	384	402
Actuarial loss		1,443	(610)
Defined Benefit Plan, Benefit Obligation, Payment for Settlement		(5,833)
Benefits paid		(483)	(505)
Benefit obligation - end of year		6,214	10,712	11,443
Change in plan assets:
Balance, beginning of year		8,649	9,350
Actual return on plan assets		1,180	(647)
Employer contributions		1,117	451
Defined Benefit Plan, Plan Assets, Payment for Settlement		(5,833)
Benefits paid		(483)	(505)
Balance, end of year		4,630	8,649	$ 9,350
Reconciliation:
Funded status		(1,584)	(2,063)
Accrued pension cost		$ (1,584)	$ (2,063)
Assumptions:
Discount rate		3.00%	4.00%
Expected return on plan assets		6.00%	6.00%	6.00%
FPU Pension Plan
Change in benefit obligation:
Benefit obligation - beginning of year		$ 59,377	$ 64,664
Interest cost		2,452	2,339	$ 2,482
Actuarial loss		6,508	(4,739)
Benefits paid		(3,033)	(2,887)
Benefit obligation - end of year		65,304	59,377	64,664
Change in plan assets:
Balance, beginning of year		43,601	48,396
Actual return on plan assets		7,978	(3,113)
Employer contributions		1,157	1,205
Benefits paid		(3,033)	(2,887)
Balance, end of year		49,703	43,601	$ 48,396
Reconciliation:
Funded status		(15,601)	(15,776)
Accrued pension cost		$ (15,601)	$ (15,776)
Assumptions:
Discount rate		3.25%	4.25%
Expected return on plan assets		6.50%	6.50%	6.50%
Chesapeake SERP
Change in benefit obligation:
Benefit obligation - beginning of year		$ 2,285	$ 2,428
Interest cost		74	83
Actuarial loss		159	(74)
Benefits paid		(361)	(152)
Benefit obligation - end of year		2,157	2,285	$ 2,428
Change in plan assets:
Employer contributions		361	152
Benefits paid		(361)	(152)
Reconciliation:
Funded status		(2,157)	(2,285)
Accrued pension cost		$ (2,157)	$ (2,285)
Assumptions:
Discount rate		3.00%	4.00%
Chesapeake Postretirement Plan
Change in benefit obligation:
Benefit obligation - beginning of year		$ 1,002	$ 1,128
Interest cost		39	38	41
Plan participants contributions		149	136
Actuarial loss		73	(131)
Benefits paid		(163)	(169)
Benefit obligation - end of year		1,100	1,002	1,128
Change in plan assets:
Balance, beginning of year		0	0
Employer contributions	[1]	14	33
Plan participants contributions		149	136
Benefits paid		(163)	(169)
Balance, end of year		0	0	0
Reconciliation:
Funded status		(1,100)	(1,002)
Accrued pension cost		$ (1,100)	$ (1,002)
Assumptions:
Discount rate		3.00%	4.00%
FPU Medical Plan
Change in benefit obligation:
Benefit obligation - beginning of year		$ 1,187	$ 1,287
Interest cost		48	47	50
Plan participants contributions		38	41
Actuarial loss		47	(89)
Benefits paid		(96)	(99)
Benefit obligation - end of year		1,224	1,187	1,287
Change in plan assets:
Balance, beginning of year		0	0
Employer contributions	[1]	58	58
Plan participants contributions		38	41
Benefits paid		(96)	(99)
Balance, end of year		0	0	$ 0
Reconciliation:
Funded status		(1,224)	(1,187)
Accrued pension cost		$ (1,224)	$ (1,187)
Assumptions:
Discount rate		3.25%	4.25%
[1]	The Chesapeake Postretirement Plan does not receive a Medicare Part-D subsidy. The FPU Medical Plan did not receive a significant subsidy for the post-merger period.

Employee Benefit Plans - Sche_2

Employee Benefit Plans - Schedule of Amounts Not Yet Reflected in Net Periodic Benefit Cost and Included in Accumulated Other Comprehensive Income Loss or Regulatory Assets (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Interest Cost		$ 74	$ 83	$ 89
Prior service cost (credit)		(447)
Net loss		22,727
Total		22,280
Accumulated other comprehensive loss pre-tax		6,641
Post-merger regulatory asset		15,639
Subtotal		22,280
Pre-merger regulatory asset		6
Total unrecognized cost		22,286
Chesapeake Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Interest Cost		375	384	402
Prior service cost (credit)		0
Net loss		2,241
Total		2,241
Accumulated other comprehensive loss pre-tax	[1]	2,241
Post-merger regulatory asset		0
Subtotal		2,241
Pre-merger regulatory asset		0
Total unrecognized cost		2,241
Defined Benefit Plan, Expected Return (Loss) on Plan Assets		487	542	495
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year		(391)	(343)	(399)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement		(1,982)	0	0
Net Periodic Cost Benefit		2,261	185	306
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)		2,261	185	306
Amortization Of Pre Merger Regulatory Asset		$ 0	$ 0	$ 0
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate		3.00%	3.50%	3.75%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets		6.00%	6.00%	6.00%
FPU Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Interest Cost		$ 2,452	$ 2,339	$ 2,482
Prior service cost (credit)		0
Net loss		19,339
Total		19,339
Accumulated other comprehensive loss pre-tax	[1]	3,674
Post-merger regulatory asset		15,665
Subtotal		19,339
Pre-merger regulatory asset		0
Total unrecognized cost		19,339
Defined Benefit Plan, Expected Return (Loss) on Plan Assets		2,770	3,091	2,779
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year		(505)	(404)	(513)
Net Periodic Cost Benefit		187	(348)	216
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)		730	413	977
Amortization Of Pre Merger Regulatory Asset		$ 543	$ 761	$ 761
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate		4.25%	3.75%	4.00%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets		6.50%	6.50%	6.50%
Chesapeake SERP
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Interest Cost		$ 74	$ 83
Prior service cost (credit)		0
Net loss		575
Total		575
Accumulated other comprehensive loss pre-tax	[1]	575
Post-merger regulatory asset		0
Subtotal		575
Pre-merger regulatory asset		0
Total unrecognized cost		575
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year		(85)	(101)	$ (87)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement		(58)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)		$ 217	$ 184	$ 176
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate		4.00%	3.50%	3.75%
Chesapeake Postretirement Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Interest Cost		$ 39	$ 38	$ 41
Prior service cost (credit)		(447)
Net loss		604
Total		157
Accumulated other comprehensive loss pre-tax	[1]	157
Post-merger regulatory asset		0
Subtotal		157
Pre-merger regulatory asset		0
Total unrecognized cost		157
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year		(46)	(58)	(53)
Net Periodic Cost Benefit		8	19	17
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)		$ 8	$ 19	$ 17
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate		4.00%	3.50%	3.75%
FPU Medical Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Interest Cost		$ 48	$ 47	$ 50
Prior service cost (credit)		0
Net loss		(32)
Total		(32)
Accumulated other comprehensive loss pre-tax	[1]	(6)
Post-merger regulatory asset		(26)
Subtotal		(32)
Pre-merger regulatory asset		6
Total unrecognized cost		(26)
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year		0	0	0
Net Periodic Cost Benefit		48	47	50
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)		56	55	58
Amortization Of Pre Merger Regulatory Asset		$ 8	$ 8	$ 8
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate		4.25%	3.75%	4.00%
[1]	The total amount of accumulated other comprehensive loss recorded on our consolidated balance sheet as of December 31, 2019 is net of income tax benefits of $1.7 million .

Employee Benefit Plans - Sche_3

Employee Benefit Plans - Schedule of Amounts Not Yet Reflected in Net Periodic Benefit Cost and Included in Accumulated Other Comprehensive Income Loss or Regulatory Assets (Phantoms) (Detail) $ in Millions	Dec. 31, 2019USD ($)
Disclosure Employee Benefit Plans Schedule Of Amounts Not Yet Reflected In Net Periodic Benefit Cost And Included In Accumulated Other Comprehensive Income Loss Or Regulatory Assets [Abstract]
Income tax benefits	$ 1.7

Employee Benefit Plans - Sche_4

Employee Benefit Plans - Schedule of Assets by Investment Type (Detail)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Chesapeake Pension Plan
Asset Category
Percentage of assets by investment type	100.00%	100.00%	100.00%
Chesapeake Pension Plan | Investments in equity securities
Asset Category
Percentage of assets by investment type	0.00%	49.00%	53.00%
Chesapeake Pension Plan | Debt securities
Asset Category
Percentage of assets by investment type	92.00%	41.00%	38.00%
Chesapeake Pension Plan | Other
Asset Category
Percentage of assets by investment type	8.00%	10.00%	9.00%
FPU Pension Plan
Asset Category
Percentage of assets by investment type	100.00%	100.00%	100.00%
FPU Pension Plan | Investments in equity securities
Asset Category
Percentage of assets by investment type	53.00%	50.00%	55.00%
FPU Pension Plan | Debt securities
Asset Category
Percentage of assets by investment type	37.00%	41.00%	37.00%
FPU Pension Plan | Other
Asset Category
Percentage of assets by investment type	10.00%	9.00%	8.00%

Employee Benefit Plans - Sche_5

Employee Benefit Plans - Schedule of Asset Allocation Strategy (Detail)	Dec. 31, 2019
Minimum | Domestic Equities
Debt and Equity Securities, FV-NI [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	14.00%
Minimum | Foreign Equities
Debt and Equity Securities, FV-NI [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	13.00%
Minimum | Fixed Income
Debt and Equity Securities, FV-NI [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	26.00%
Minimum | Alternative Strategies
Debt and Equity Securities, FV-NI [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	6.00%
Minimum | Diversifying Assets
Debt and Equity Securities, FV-NI [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	7.00%
Minimum | Cash
Debt and Equity Securities, FV-NI [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%
Maximum | Domestic Equities
Debt and Equity Securities, FV-NI [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	32.00%
Maximum | Foreign Equities
Debt and Equity Securities, FV-NI [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	25.00%
Maximum | Fixed Income
Debt and Equity Securities, FV-NI [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	40.00%
Maximum | Alternative Strategies
Debt and Equity Securities, FV-NI [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	14.00%
Maximum | Diversifying Assets
Debt and Equity Securities, FV-NI [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	19.00%
Maximum | Cash
Debt and Equity Securities, FV-NI [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	5.00%

Employee Benefit Plans - Summar

Employee Benefit Plans - Summary of Pension Plan Assets (Detail) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets		$ 54,333	$ 52,250
Total Pension Plan Assets, excluding investments measured at net asset value		47,316	46,692
Investments measured at net asset value	[1]	7,017	5,558
Investments in equity securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets		20,477	20,499
Investments in equity securities | Us Large Cap Equity Securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[2]	3,553	3,399
Investments in equity securities | Us Mid Cap Equity Securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[2]	1,604	1,478
Investments in equity securities | United States Equity Small Cap
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[2]	726	670
Investments in equity securities | International All Cap Equity
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[3]	9,855	9,226
Investments in equity securities | Alternative Strategies
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[4]	4,739	5,726
Debt securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets		21,696	21,448
Debt securities | Fixed Income
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[5]	19,220	18,630
Debt securities | High Yield Asset Backed Securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[5]	2,476	2,818
Other
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets		5,143	4,745
Other | Commodities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[6]	1,708	1,902
Other | Real Estate
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[7]	2,288	2,216
Other | Guaranteed deposit
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[8]	1,147	627
Quoted Prices in Active Markets (Level 1)
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets		46,169	46,065
Quoted Prices in Active Markets (Level 1) | Investments in equity securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets		20,477	20,499
Quoted Prices in Active Markets (Level 1) | Investments in equity securities | Us Large Cap Equity Securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[2]	3,553	3,399
Quoted Prices in Active Markets (Level 1) | Investments in equity securities | Us Mid Cap Equity Securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[2]	1,604	1,478
Quoted Prices in Active Markets (Level 1) | Investments in equity securities | United States Equity Small Cap
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[2]	726	670
Quoted Prices in Active Markets (Level 1) | Investments in equity securities | International All Cap Equity
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[3]	9,855	9,226
Quoted Prices in Active Markets (Level 1) | Investments in equity securities | Alternative Strategies
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[4]	4,739	5,726
Quoted Prices in Active Markets (Level 1) | Debt securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets		21,696	21,448
Quoted Prices in Active Markets (Level 1) | Debt securities | Fixed Income
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[5]	19,220	18,630
Quoted Prices in Active Markets (Level 1) | Debt securities | High Yield Asset Backed Securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[5]	2,476	2,818
Quoted Prices in Active Markets (Level 1) | Other
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets		3,996	4,118
Quoted Prices in Active Markets (Level 1) | Other | Commodities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[6]	1,708	1,902
Quoted Prices in Active Markets (Level 1) | Other | Real Estate
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[7]	2,288	2,216
Quoted Prices in Active Markets (Level 1) | Other | Guaranteed deposit
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[8]	0	0
Significant Other Observable Inputs (Level 2)
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets		0	0
Significant Other Observable Inputs (Level 2) | Investments in equity securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets		0	0
Significant Other Observable Inputs (Level 2) | Investments in equity securities | Us Large Cap Equity Securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[2]	0	0
Significant Other Observable Inputs (Level 2) | Investments in equity securities | Us Mid Cap Equity Securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[2]	0	0
Significant Other Observable Inputs (Level 2) | Investments in equity securities | United States Equity Small Cap
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[2]	0	0
Significant Other Observable Inputs (Level 2) | Investments in equity securities | International All Cap Equity
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[3]	0	0
Significant Other Observable Inputs (Level 2) | Investments in equity securities | Alternative Strategies
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[4]	0	0
Significant Other Observable Inputs (Level 2) | Debt securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets		0	0
Significant Other Observable Inputs (Level 2) | Debt securities | Fixed Income
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[5]	0	0
Significant Other Observable Inputs (Level 2) | Debt securities | High Yield Asset Backed Securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[5]	0	0
Significant Other Observable Inputs (Level 2) | Other
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets		0	0
Significant Other Observable Inputs (Level 2) | Other | Commodities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[6]	0	0
Significant Other Observable Inputs (Level 2) | Other | Real Estate
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[7]	0	0
Significant Other Observable Inputs (Level 2) | Other | Guaranteed deposit
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[8]	0	0
Significant Unobservable Inputs (Level 3)
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets		1,147	627	$ 436
Significant Unobservable Inputs (Level 3) | Investments in equity securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets		0	0
Significant Unobservable Inputs (Level 3) | Investments in equity securities | Us Large Cap Equity Securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[2]	0	0
Significant Unobservable Inputs (Level 3) | Investments in equity securities | Us Mid Cap Equity Securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[2]	0	0
Significant Unobservable Inputs (Level 3) | Investments in equity securities | United States Equity Small Cap
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[2]	0	0
Significant Unobservable Inputs (Level 3) | Investments in equity securities | International All Cap Equity
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[3]	0	0
Significant Unobservable Inputs (Level 3) | Investments in equity securities | Alternative Strategies
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[4]	0	0
Significant Unobservable Inputs (Level 3) | Debt securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets		0	0
Significant Unobservable Inputs (Level 3) | Debt securities | Fixed Income
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[5]	0	0
Significant Unobservable Inputs (Level 3) | Debt securities | High Yield Asset Backed Securities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[5]	0	0
Significant Unobservable Inputs (Level 3) | Other
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets		1,147	627
Significant Unobservable Inputs (Level 3) | Other | Commodities
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[6]	0	0
Significant Unobservable Inputs (Level 3) | Other | Real Estate
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[7]	0	0
Significant Unobservable Inputs (Level 3) | Other | Guaranteed deposit
Debt and Equity Securities, FV-NI [Line Items]
Total Pension Plan Assets	[8]	$ 1,147	$ 627
[1]	Certain investments that were measured at net asset value per share have not been classified in the fair value hierarchy. These amounts are presented to reconcile to total pension plan assets.
[2]	Includes funds that invest primarily in United States common stocks.
[3]	Includes funds that invest primarily in foreign equities and emerging markets equities.
[4]	Includes funds that actively invest in both equity and debt securities, funds that sell short securities and funds that provide long-term capital appreciation. The funds may invest in debt securities below investment grade.
[5]	Includes funds that invest in investment grade and fixed income securities.
[6]	Includes funds that invest primarily in commodity-linked derivative instruments and fixed income securities.
[7]	Includes funds that invest primarily in real estate.
[8]	Includes investment in a group annuity product issued by an insurance company.

Employee Benefit Plans - Summ_2

Employee Benefit Plans - Summary of Changes in Fair Value of Level 3 Investments (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets, Excluding Net Asset Value Investments		$ 47,316	$ 46,692
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year		52,250
Balance, end of year		54,333	52,250
Defined Benefit Plan, Alternative Investments, Fair Value of Plan Assets	[1]	7,017	5,558
Quoted Prices in Active Markets (Level 1)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year		46,065
Balance, end of year		46,169	46,065
Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year		0
Balance, end of year		0	0
Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year		627	436
Purchases		2,274	1,674
Transfers in		3,090	2,375
Disbursements		(4,907)	(3,872)
Investment Income		63	14
Balance, end of year		1,147	627
Investments in equity securities
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year		20,499
Balance, end of year		20,477	20,499
Investments in equity securities | Quoted Prices in Active Markets (Level 1)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year		20,499
Balance, end of year		20,477	20,499
Investments in equity securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year		0
Balance, end of year		0	0
Investments in equity securities | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year		0
Balance, end of year		0	0
Debt securities
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year		21,448
Balance, end of year		21,696	21,448
Debt securities | Quoted Prices in Active Markets (Level 1)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year		21,448
Balance, end of year		21,696	21,448
Debt securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year		0
Balance, end of year		0	0
Debt securities | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year		0
Balance, end of year		0	0
Other Investments [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year		4,745
Balance, end of year		5,143	4,745
Other Investments [Member] | Quoted Prices in Active Markets (Level 1)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year		4,118
Balance, end of year		3,996	4,118
Other Investments [Member] | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year		0
Balance, end of year		0	0
Other Investments [Member] | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year		627
Balance, end of year		1,147	627
Us Large Cap Equity Securities | Investments in equity securities
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[2]	3,399
Balance, end of year	[2]	3,553	3,399
Us Large Cap Equity Securities | Investments in equity securities | Quoted Prices in Active Markets (Level 1)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[2]	3,399
Balance, end of year	[2]	3,553	3,399
Us Large Cap Equity Securities | Investments in equity securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[2]	0
Balance, end of year	[2]	0	0
Us Large Cap Equity Securities | Investments in equity securities | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[2]	0
Balance, end of year	[2]	0	0
Us Mid Cap Equity Securities | Investments in equity securities
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[2]	1,478
Balance, end of year	[2]	1,604	1,478
Us Mid Cap Equity Securities | Investments in equity securities | Quoted Prices in Active Markets (Level 1)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[2]	1,478
Balance, end of year	[2]	1,604	1,478
Us Mid Cap Equity Securities | Investments in equity securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[2]	0
Balance, end of year	[2]	0	0
Us Mid Cap Equity Securities | Investments in equity securities | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[2]	0
Balance, end of year	[2]	0	0
United States Equity Small Cap | Investments in equity securities
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[2]	670
Balance, end of year	[2]	726	670
United States Equity Small Cap | Investments in equity securities | Quoted Prices in Active Markets (Level 1)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[2]	670
Balance, end of year	[2]	726	670
United States Equity Small Cap | Investments in equity securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[2]	0
Balance, end of year	[2]	0	0
United States Equity Small Cap | Investments in equity securities | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[2]	0
Balance, end of year	[2]	0	0
International All Cap Equity | Investments in equity securities
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[3]	9,226
Balance, end of year	[3]	9,855	9,226
International All Cap Equity | Investments in equity securities | Quoted Prices in Active Markets (Level 1)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[3]	9,226
Balance, end of year	[3]	9,855	9,226
International All Cap Equity | Investments in equity securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[3]	0
Balance, end of year	[3]	0	0
International All Cap Equity | Investments in equity securities | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[3]	0
Balance, end of year	[3]	0	0
Alternative Strategies | Investments in equity securities
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[4]	5,726
Balance, end of year	[4]	4,739	5,726
Alternative Strategies | Investments in equity securities | Quoted Prices in Active Markets (Level 1)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[4]	5,726
Balance, end of year	[4]	4,739	5,726
Alternative Strategies | Investments in equity securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[4]	0
Balance, end of year	[4]	0	0
Alternative Strategies | Investments in equity securities | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[4]	0
Balance, end of year	[4]	0	0
Fixed Income Securities [Member] | Debt securities
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[5]	18,630
Balance, end of year	[5]	19,220	18,630
Fixed Income Securities [Member] | Debt securities | Quoted Prices in Active Markets (Level 1)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[5]	18,630
Balance, end of year	[5]	19,220	18,630
Fixed Income Securities [Member] | Debt securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[5]	0
Balance, end of year	[5]	0	0
Fixed Income Securities [Member] | Debt securities | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[5]	0
Balance, end of year	[5]	0	0
High Yield Asset Backed Securities | Debt securities
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[5]	2,818
Balance, end of year	[5]	2,476	2,818
High Yield Asset Backed Securities | Debt securities | Quoted Prices in Active Markets (Level 1)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[5]	2,818
Balance, end of year	[5]	2,476	2,818
High Yield Asset Backed Securities | Debt securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[5]	0
Balance, end of year	[5]	0	0
High Yield Asset Backed Securities | Debt securities | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[5]	0
Balance, end of year	[5]	0	0
Commodities | Other Investments [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[6]	1,902
Balance, end of year	[6]	1,708	1,902
Commodities | Other Investments [Member] | Quoted Prices in Active Markets (Level 1)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[6]	1,902
Balance, end of year	[6]	1,708	1,902
Commodities | Other Investments [Member] | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[6]	0
Balance, end of year	[6]	0	0
Commodities | Other Investments [Member] | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[6]	0
Balance, end of year	[6]	0	0
Real Estate [Member] | Other Investments [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[7]	2,216
Balance, end of year	[7]	2,288	2,216
Real Estate [Member] | Other Investments [Member] | Quoted Prices in Active Markets (Level 1)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[7]	2,216
Balance, end of year	[7]	2,288	2,216
Real Estate [Member] | Other Investments [Member] | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[7]	0
Balance, end of year	[7]	0	0
Real Estate [Member] | Other Investments [Member] | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[7]	0
Balance, end of year	[7]	0	0
Guaranteed deposit | Other Investments [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[8]	627
Balance, end of year	[8]	1,147	627
Guaranteed deposit | Other Investments [Member] | Quoted Prices in Active Markets (Level 1)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[8]	0
Balance, end of year	[8]	0	0
Guaranteed deposit | Other Investments [Member] | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[8]	0
Balance, end of year	[8]	0	0
Guaranteed deposit | Other Investments [Member] | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance, beginning of year	[8]	627
Balance, end of year	[8]	$ 1,147	$ 627
[1]	Certain investments that were measured at net asset value per share have not been classified in the fair value hierarchy. These amounts are presented to reconcile to total pension plan assets.
[2]	Includes funds that invest primarily in United States common stocks.
[3]	Includes funds that invest primarily in foreign equities and emerging markets equities.
[4]	Includes funds that actively invest in both equity and debt securities, funds that sell short securities and funds that provide long-term capital appreciation. The funds may invest in debt securities below investment grade.
[5]	Includes funds that invest in investment grade and fixed income securities.
[6]	Includes funds that invest primarily in commodity-linked derivative instruments and fixed income securities.
[7]	Includes funds that invest primarily in real estate.
[8]	Includes investment in a group annuity product issued by an insurance company.

Employee Benefit Plans - Compon

Employee Benefit Plans - Component of Net Periodic Pension Cost (Benefit) (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Components of net periodic cost:
Interest cost		$ 74	$ 83	$ 89
Expected Amortization Of Pre Merger Regulatory Asset		0
Assumptions
Defined Benefit Plan, Plan Assets, Amount		54,333	52,250
Chesapeake Postretirement Plan
Components of net periodic cost:
Interest cost		39	38	41
Amortization of prior service cost		(77)	(77)	(77)
Actuarial (gain) loss		46	58	53
Net periodic pension cost		8	19	17
Expected Amortization Of Pre Merger Regulatory Asset			0	0
Net periodic postretirement cost		$ 8	$ 19	$ 17
Assumptions
Discount rate		4.00%	3.50%	3.75%
Defined Benefit Plan, Benefit Obligation, Contributions by Plan Participant		$ 149	$ 136
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		73	(131)
Defined Benefit Plan, Benefit Obligation, Benefits Paid		(163)	(169)
Defined Benefit Plan, Plan Assets, Amount		0	0	$ 0
Defined Benefit Plan, Plan Assets, Contributions by Employer	[1]	14	33
Defined Benefit Plan, Plan Assets, Contributions by Plan Participant		149	136
Defined Benefit Plan, Plan Assets, Benefits Paid		(163)	(169)
Funded status		(1,100)	(1,002)
Accrued pension cost		$ (1,100)	$ (1,002)
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate		3.00%	4.00%
FPU Medical Plan
Components of net periodic cost:
Interest cost		$ 48	$ 47	50
Amortization of prior service cost		0	0	0
Actuarial (gain) loss		0	0	0
Net periodic pension cost		48	47	50
Amortization of pre-merger regulatory asset		8	8	8
Net periodic postretirement cost		$ 56	$ 55	$ 58
Assumptions
Discount rate		4.25%	3.75%	4.00%
Defined Benefit Plan, Benefit Obligation, Contributions by Plan Participant		$ 38	$ 41
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		47	(89)
Defined Benefit Plan, Benefit Obligation, Benefits Paid		(96)	(99)
Defined Benefit Plan, Plan Assets, Amount		0	0	$ 0
Defined Benefit Plan, Plan Assets, Contributions by Employer	[1]	58	58
Defined Benefit Plan, Plan Assets, Contributions by Plan Participant		38	41
Defined Benefit Plan, Plan Assets, Benefits Paid		(96)	(99)
Funded status		(1,224)	(1,187)
Accrued pension cost		$ (1,224)	$ (1,187)
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate		3.25%	4.25%
Chesapeake SERP
Components of net periodic cost:
Interest cost		$ 74	$ 83
Actuarial (gain) loss		85	101	87
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement		58
Net periodic postretirement cost		$ 217	$ 184	$ 176
Assumptions
Discount rate		4.00%	3.50%	3.75%
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		$ 159	$ (74)
Defined Benefit Plan, Benefit Obligation, Benefits Paid		(361)	(152)
Defined Benefit Plan, Plan Assets, Contributions by Employer		361	152
Defined Benefit Plan, Plan Assets, Benefits Paid		(361)	(152)
Funded status		(2,157)	(2,285)
Accrued pension cost		$ (2,157)	$ (2,285)
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate		3.00%	4.00%
Chesapeake Pension Plan
Components of net periodic cost:
Interest cost		$ 375	$ 384	$ 402
Expected return on assets		(487)	(542)	(495)
Actuarial (gain) loss		391	343	399
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement		1,982	0	0
Net periodic pension cost		2,261	185	306
Amortization of pre-merger regulatory asset		0	0	0
Net periodic postretirement cost		$ 2,261	$ 185	$ 306
Assumptions
Discount rate		3.00%	3.50%	3.75%
Expected return on plan assets		6.00%	6.00%	6.00%
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		$ 1,443	$ (610)
Defined Benefit Plan, Benefit Obligation, Benefits Paid		(483)	(505)
Defined Benefit Plan, Plan Assets, Amount		4,630	8,649	$ 9,350
Defined Benefit Plan, Plan Assets, Contributions by Employer		1,117	451
Defined Benefit Plan, Plan Assets, Benefits Paid		(483)	(505)
Funded status		(1,584)	(2,063)
Accrued pension cost		$ (1,584)	$ (2,063)
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate		3.00%	4.00%
FPU Pension Plan
Components of net periodic cost:
Interest cost		$ 2,452	$ 2,339	2,482
Expected return on assets		(2,770)	(3,091)	(2,779)
Actuarial (gain) loss		505	404	513
Net periodic pension cost		187	(348)	216
Amortization of pre-merger regulatory asset		543	761	761
Net periodic postretirement cost		$ 730	$ 413	$ 977
Assumptions
Discount rate		4.25%	3.75%	4.00%
Expected return on plan assets		6.50%	6.50%	6.50%
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)		$ 6,508	$ (4,739)
Defined Benefit Plan, Benefit Obligation, Benefits Paid		(3,033)	(2,887)
Defined Benefit Plan, Plan Assets, Amount		49,703	43,601	$ 48,396
Defined Benefit Plan, Plan Assets, Contributions by Employer		1,157	1,205
Defined Benefit Plan, Plan Assets, Benefits Paid		(3,033)	(2,887)
Funded status		(15,601)	(15,776)
Accrued pension cost		$ (15,601)	$ (15,776)
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate		3.25%	4.25%
[1]	The Chesapeake Postretirement Plan does not receive a Medicare Part-D subsidy. The FPU Medical Plan did not receive a significant subsidy for the post-merger period.

Employee Benefit Plans - Amount

Employee Benefit Plans - Amounts in Accumulated Other Comprehensive Income/Loss and Regulatory Asset (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Chesapeake Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Amortization of pre-merger regulatory asset	$ 0	$ 0	$ 0
FPU Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Amortization of pre-merger regulatory asset	543	761	761
FPU Medical Plan
Defined Benefit Plan Disclosure [Line Items]
Amortization of pre-merger regulatory asset	$ 8	$ 8	$ 8

Employee Benefit Plans - Sche_6

Employee Benefit Plans - Schedule of Estimated Future Benefit Payments (Detail) $ in Thousands	Dec. 31, 2019USD ($)
Chesapeake Pension Plan
Defined Benefit Plan, Expected Future Benefit Payments, Maturity [Line Items]
2017	$ 115	[1]
2018	368	[1]
2019	106	[1]
2020	927	[1]
2021	111	[1]
Years 2022 through 2026	2,300	[1]
FPU Pension Plan
Defined Benefit Plan, Expected Future Benefit Payments, Maturity [Line Items]
2017	3,281	[1]
2018	3,348	[1]
2019	3,424	[1]
2020	3,498	[1]
2021	3,549	[1]
Years 2022 through 2026	18,429	[1]
Chesapeake SERP
Defined Benefit Plan, Expected Future Benefit Payments, Maturity [Line Items]
2017	151	[2]
2018	150	[2]
2019	148	[2]
2020	146	[2]
2021	144	[2]
Years 2022 through 2026	748	[2]
Chesapeake Postretirement Plan
Defined Benefit Plan, Expected Future Benefit Payments, Maturity [Line Items]
2017	90	[2]
2018	87	[2]
2019	85	[2]
2020	67	[2]
2021	64	[2]
Years 2022 through 2026	264	[2]
FPU Medical Plan
Defined Benefit Plan, Expected Future Benefit Payments, Maturity [Line Items]
2017	86	[2]
2018	90	[2]
2019	91	[2]
2020	79	[2]
2021	80	[2]
Years 2022 through 2026	$ 389	[2]
[1]	The pension plan is funded; therefore, benefit payments are expected to be paid out of the plan assets.
[2]	Benefit payments are expected to be paid out of our general funds.

Employee Benefit Plans Employee

Employee Benefit Plans Employee benefit plans phantoms (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Chesapeake Pension Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Funded status	$ (1,584)	$ (2,063)

Share-Based Compensation - Addi

Share-Based Compensation - Additional Information (Detail) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)$ / sharesshares		Dec. 31, 2018USD ($)$ / sharesshares	Dec. 31, 2017USD ($)shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	43,032
Unrecognized compensation expense related to the awards to Non employee directors | $	$ 4,300
Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number	14,107
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures and Expirations	2,569
Shares reserved for issuance	831,183
Number of Shares, Granted	751		792
Number of shares withheld	7,635		16,918	10,269
Payments of employees' tax obligations to taxing authorities	3
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount | $	$ 1,100
SICP Awards to Non-employee directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amortization of expense equally over a service period	1 year
Unrecognized compensation expense related to the awards to Non employee directors | $	$ 200
Weighted average grant-date fair value of awards granted | $ / shares	$ 93.14		$ 75.70
Total [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Granted	6,759		7,128
Awards to non-employee director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Granted	254		276
Weighted average grant-date fair value of awards granted | $ / shares	$ 95.83		$ 81.30
SICP Awards to Key Employees
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, Vested in Period, Weighted Average Grant Date Fair Value | $ / shares	$ 67,080		$ 47.39
Number of Shares, Granted	88,048	[1]	49,494
Weighted average grant-date fair value of awards granted | $ / shares	$ 92,740	[1]	$ 67.76
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Nonvested | $	$ 15,100		$ 10,700	$ 10,400
Stock and Incentive Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance	449,868
[1]	Includes 43,032

Share-Based Compensation Plan_2

Share-Based Compensation Plans - Share-Based Compensation Amounts Included in Net Income (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation expense	$ 4,279	$ 3,410	$ 2,490
Less: tax benefit	(1,117)	(934)	(1,003)
Share-Based Compensation amounts included in net income	3,162	2,476	1,487
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	4,300
SICP Awards to Non-employee directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation expense	620	539	540
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	200
SICP Awards to Key Employees
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, Aggregate Intrinsic Value, Nonvested	15,100	10,700	10,400
Total compensation expense	$ 3,659	$ 2,871	$ 1,950

Share-Based Compensation Plan_3

Share-Based Compensation Plans - Summary of Stock Activity Non-employee directors (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Shares, Granted	751	792
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 4,300
SICP Awards to Non-employee directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period For Amortization Of Share Based Expenses	1 year
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted Average Grant Date Fair Value, Granted	$ 93.14	$ 75.70
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 200

Share-Based Compensation Plan_4

Share-Based Compensation Plans - Summary of Stock Activity under SICP - Key employees (Detail) - $ / shares		12 Months Ended
		Dec. 31, 2019		Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Shares, Granted		751		792
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number		14,107
SICP Awards to Key Employees
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Shares, Outstanding Beginning Balance		131,741		132,642
Number of Shares, Granted		88,048	[1]	49,494
Number of Shares, Vested		(25,831)		(29,786)
Number of Shares, Expired		(15,086)		(3,933)
Number of Shares, Outstanding Ending Balance		157,817		131,741
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted Average Grant Date Fair Value, Outstanding Beginning Balance		$ 67.24		$ 59.31
Weighted Average Grant Date Fair Value, Granted		92,740	[1]	67.76
Weighted Average Grant Date Fair Value, Vested		67,080		47.39
Weighted Average Grant Date Fair Value, Expired		69,280		49.66
Weighted Average Grant Date Fair Value, Outstanding Ending Balance		$ 80,280		67.24
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	[2]	21,055
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	[2]	$ 71,670
Accelerated Vested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted Average Grant Date Fair Value, Vested				$ 75.78
Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number				16,676
[1]	Includes 43,032
[2]	(2) In conjunction with the retirement of two key employees during 2019, these shares were forfeited for the remainder of the service periods associated with awards granted during their employment with the Company.

Share-Based Compensation Plan_5

Share-Based Compensation Plans Shares Withheld and Tax Benefits Associated With Share-Based Payments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Payment Arrangement [Abstract]
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation	7,635	16,918	10,269
Payment, Tax Withholding, Share-based Payment Arrangement	$ 692	$ 1,210	$ 692
Proceeds and Excess Tax Benefit from Share-based Compensation	$ 0		$ 349

Rates and Other Regulatory Ac_4

Rates and Other Regulatory Activities - Additional Information (Detail) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019USD ($)mi	Sep. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2019USD ($)dekatherm / dmi	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)
Rates and Other Regulatory Activities [Line Items]
Restricted Payment	$ 227,500								$ 227,500
Regulatory Assets	78,551				$ 77,218				78,551	$ 77,218
Revenues	$ 131,973	$ 92,626	$ 94,541	$ 160,464	$ 134,214	$ 93,400	$ 93,872	$ 168,831	479,604	$ 490,316	$ 449,646
Depreciation Expense Decrease from Depreciation Study Rate Change									$ 900
Electric Limited Proceedings [Member]
Rates and Other Regulatory Activities [Line Items]
Number of Years to Recover Storm Related Costs									2 years
Extent of Customers Losing Service									100.00%
Amounts Spent to Restore Service									$ 65,000
Number of Term Notes Issued for Hurricane Michael	2								2
Number of Months for Term Notes to Finance Hurricane Michael									13 months
Dollar Amount of Term Notes to Finance Hurricane Michael Costs									$ 30,000
Asset Recovery Damaged Property Costs, Noncurrent	$ 1,500								1,500
Deferred Storm and Property Reserve Deficiency, Noncurrent	$ 800								$ 800
Basis Plus LIBOR for Term Notes to Finance Hurricane Michael Costs	75								75
Peninsula Pipeline [Member] | Callahan Project [Member]
Rates and Other Regulatory Activities [Line Items]
Number of Pipeline Miles | mi	26								26
Diameter of Pipe | mi	16								16
Eastern Shore Gas Company | Del-Mar Pathway Project [Domain]
Rates and Other Regulatory Activities [Line Items]
firm natural gas transportation deliverability | dekatherm / d									14,300
Eastern Shore Gas Company | Del-Mar Pathway Project [Member]
Rates and Other Regulatory Activities [Line Items]
Number of Pipeline Miles | mi	6								6
number of customers									4
Number of Mainline Pipeline Miles | mi	13								13
Florida Public Utilities Company [Member]
Rates and Other Regulatory Activities [Line Items]
Restricted Payment	$ 2,500								$ 2,500
Business Acquisition Premium Paid	$ 34,200								$ 34,200
Elkton Gas [Member] | Regulated Energy [Member]
Rates and Other Regulatory Activities [Line Items]
Number of customers acquired through acquisition									7,000

Rates and Other Regulatory Ac_5

Rates and Other Regulatory Activities Regulatory Assets and Liabilities (Details) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Rates and Other Regulatory Activities [Line Items]
Regulatory Assets		$ 78,551	$ 77,218
Regulatory Liabilities		133,735	142,922
Self Insured Liabilities [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	[1]	873	947
Overrecovered Gas And Fuel Costs [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities		2,724	5,856
Storm Reserve [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	[1]	1,437	677
Accrued asset removal cost
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	[2]	36,767	42,401
Deferred Income Tax Due to Rate Change [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities	[3]	89,191	91,236
Other Regulatory Liability [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Liabilities		75	242
Underrecovered Gas And Fuel Costs [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Assets	[4]	5,144	4,631
Under-recovered GRIP Revenue [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Assets	[5]	0	165
Regulatory Liabilities	[5]	2,668	1,563
Deferred Post Retirement Benefits [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Assets	[6]	16,311	15,517
Deferred Conversion And Development Costs [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Assets	[4]	20,881	16,727
Environmental Regulatory Assets And Expenditures [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Assets	[7]	2,241	2,731
Acquisition Adjustment [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Assets	[8]	30,329	33,255
Loss on Reacquired Debt [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Assets	[9]	869	942
Other Regulatory Asset [Member]
Rates and Other Regulatory Activities [Line Items]
Regulatory Assets		2,776	$ 3,250
Florida Public Utilities Company [Member]
Rates and Other Regulatory Activities [Line Items]
Business Acquisition Premium Paid		34,200
Regulatory Liabilities		19,218
Indiantown Gas Company
Rates and Other Regulatory Activities [Line Items]
Business Acquisition Premium Paid		$ 700
[1]	We have self-insurance and storm reserves in our Florida regulated energy operations that allow us to collect through rates amounts to be used against general claims, storm restoration costs and other losses as they are incurred.
[2]	See Note 1 , Summary of Significant Accounting Policies, for additional information on our asset removal cost policies.
[3]	9) We recorded a regulatory liability for our regulated businesses related to the revaluation of accumulated deferred tax assets/liabilities as a result of the TCJA. Based upon the regulatory proceedings, we will pass back the respective portion of the excess accumulated deferred taxes to rate payers. See Note 12, Income Taxes , for additional information.
[4]	We are allowed to recover the asset or are required to pay the liability in rates. We do not earn an overall rate of return on these assets.
[5]	The Florida PSC allowed us to recover through a surcharge, capital and other program-related-costs, inclusive of an appropriate return on investment, associated with accelerating the replacement of qualifying distribution mains and services (defined as any material other than coated steel or plastic) in FPU’s natural gas distribution, Fort Meade division and Chesapeake Utilities’ Central Florida Gas division. We are allowed to recover the asset or are required to pay the liability in rates related to GRIP.
[6]	The Florida PSC allowed FPU to treat as a regulatory asset the portion of the unrecognized costs pursuant to ASC Topic 715 , Compensation - Retirement Benefits , related to its regulated operations. In 2019, we recorded as a regulatory asset the portion of pension settlement expense associated with the de-risking of the Chesapeake Pension Plan pursuant to an order from the FERC that allowed us to defer Eastern Shore's portion. See Note 17 , Employee Benefit Plans, for additional information.
[7]	All of our environmental expenditures incurred to date and our current estimate of future environmental expenditures have been approved by various PSCs for recovery. See Note 20 , Environmental Commitments and Contingencies , for additional information on our environmental contingencies.
[8]	We are allowed to include the premiums paid in various natural gas utility acquisitions in Florida in our rate bases and recover them over a specific time period pursuant to the Florida PSC approvals. We paid $34.2 million of the premium in 2009, including a gross up for income tax, because it is not tax deductible, and $0.7 million of the premium paid by FPU in 2010.
[9]	Gains and losses resulting from the reacquisition of long-term debt are amortized over future periods as adjustments to interest expense in accordance with established regulatory practice.

Rates and Other Regulatory Ac_6

Rates and Other Regulatory Activities Federal Tax Reform Impact for Regulated Businesses (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Regulatory Liabilities Related to the Federal Tax Reform Impact [Line Items]
Regulatory Liabilities	$ 133,735	$ 142,922
Eastern Shore Gas Company [Member]
Regulatory Liabilities Related to the Federal Tax Reform Impact [Line Items]
Regulatory Liabilities	34,190
Delaware natural gas division [Member]
Regulatory Liabilities Related to the Federal Tax Reform Impact [Line Items]
Regulatory Liabilities	12,847
Maryland Division [Member]
Regulatory Liabilities Related to the Federal Tax Reform Impact [Line Items]
Regulatory Liabilities	4,087
Sandpiper [Member]
Regulatory Liabilities Related to the Federal Tax Reform Impact [Line Items]
Regulatory Liabilities	3,765
Central Florida Gas Division [Member]
Regulatory Liabilities Related to the Federal Tax Reform Impact [Line Items]
Regulatory Liabilities	8,304
Florida Public Utilities Company [Member]
Regulatory Liabilities Related to the Federal Tax Reform Impact [Line Items]
Regulatory Liabilities	19,218
Fort Meade and Indiantown Divisions [Member]
Regulatory Liabilities Related to the Federal Tax Reform Impact [Line Items]
Regulatory Liabilities	294
FPU electric division [Member]
Regulatory Liabilities Related to the Federal Tax Reform Impact [Line Items]
Regulatory Liabilities	$ 5,769

Environmental Commitments and_3

Environmental Commitments and Contingencies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2019USD ($)site	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)
Environmental Commitments And Contingencies [Line Items]
Companys Exposure In Number Of Former Manufactured Gas Plant Sites | site	7
Environmental liabilities	$ 6,468,000	$ 7,638,000
Amount paid for funding requirements	1,170,000	625,000	$ 329,000
West Palm Beach Florida | Maximum
Environmental Commitments And Contingencies [Line Items]
Environmental Exit Costs, Reasonably Possible Additional Loss	15,400,000
West Palm Beach Florida | Minimum
Environmental Commitments And Contingencies [Line Items]
Environmental Exit Costs, Reasonably Possible Additional Loss	4,500,000
Winter Haven Florida | Maximum
Environmental Commitments And Contingencies [Line Items]
Environmental Remediation Expense	425,000
Seaford | Maximum
Environmental Commitments And Contingencies [Line Items]
Environmental Exit Costs, Reasonably Possible Additional Loss	465,000
Seaford | Minimum
Environmental Commitments And Contingencies [Line Items]
Environmental Exit Costs, Reasonably Possible Additional Loss	273,000
FPU
Environmental Commitments And Contingencies [Line Items]
Environmental liabilities	8,000,000	9,100,000
Approval of recovery of environmental costs	14,000,000
Environmental costs recovered	11,900,000	11,500,000
FPU | Manufactured Gas Plant
Environmental Commitments And Contingencies [Line Items]
Regulatory assets for future recovery of environmental costs	$ 2,100,000	$ 2,500,000

Other Commitments and Conting_3

Other Commitments and Contingencies - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Subsequent Event [Line Items]
Intercompany Agreements, Description	P3Y
Debt Service Coverage Ratio	1.25
Time to cure ratio	5 days
Ratio based on average number of prior quarters	6
Funds from operations interest coverage ratio minimum times	2
Total debt to capital maximum	65
Number Of Years to Collect Benefits	20 years
Total purchase obligations for 2018	$ 60,735
Total purchase obligations for 2019 - 2020	72,123
Total purchase obligations for 2021 - 2022	60,049
Total purchase obligations thereafter	201,131
Aggregate guaranteed amount	37,000
Guarantor Obligations, Current Carrying Value	24,700
Guarantor Obligations, Current Carrying Value, PESCO	16,300
Amount of letter of credit to our current primary insurance company	$ 5,400
Florida Natural Gas Distribution and Eight Flags [Member]
Subsequent Event [Line Items]
Number of Years for Asset Management Agreement	10 years

Other Commitments and Conting_4

Other Commitments and Contingencies Purchase Obligations (Details) $ in Thousands	Dec. 31, 2019USD ($)
Long-term Purchase Commitment [Line Items]
Purchase Obligation, Due in Next Twelve Months	$ 60,735
Purchase Obligation, Due in Second and Third Year	72,123
Purchase Obligation, Due in Fourth and Fifth Year	60,049
Purchase Obligation, Due after Fifth Year	201,131
Purchase Obligation	$ 394,038

Quarterly Financial Data - Sche

Quarterly Financial Data - Schedule of Quarterly Financial Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Quarterly Financial Data Schedule Of Quarterly Financial Information [Abstract]
Revenues	$ 131,973	$ 92,626	$ 94,541	$ 160,464	$ 134,214	$ 93,400	$ 93,872	$ 168,831	$ 479,604	$ 490,316	$ 449,646
Operating Income	29,642	14,358	18,164	44,123	28,873	12,879	12,238	40,853	106,287	94,843	89,730
Net Income	22,562	5,622	8,304	28,665	17,801	5,538	6,385	26,856	65,153	56,580	58,124
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent	17,169	6,246	8,913	28,814	17,796	6,090	5,705	27,271	61,142	56,862	60,326
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	(9)	(624)	(609)	(149)	$ 5	$ (552)	$ 680	$ (415)	(1,391)	$ (282)	$ (2,202)
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax	$ 5,402	$ 0	$ 0	$ 0					$ 5,402
Income (Loss) from Continuing Operations, Per Basic Share	$ 1.05	$ 0.38	$ 0.54	$ 1.76	$ 1.09	$ 0.37	$ 0.35	$ 1.67	$ 3.73	$ 3.48	$ 3.69
Earnings per share:
Basic (in usd per share)	1.38	0.34	0.51	1.75	1.09	0.34	0.39	1.64	3.97	3.46	3.56
Income (Loss) from Continuing Operations, Per Diluted Share	1.37	0.38	0.54	1.75	1.09	0.37	0.35	1.66	3.72	3.47	3.68
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax, Per Diluted Share	1.04	(0.04)	(0.04)	(0.01)	0	(0.04)	0.04	(0.02)	0.24	(0.02)	(0.13)
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share	0.33	(0.04)	(0.03)	(0.01)	0	(0.03)	0.04	(0.03)	0.24	(0.02)	(0.13)
Diluted (in usd per share)	$ 0.33	$ 0.34	$ 0.50	$ 1.74	$ 1.09	$ 0.33	$ 0.39	$ 1.64	$ 3.96	$ 3.45	$ 3.55

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 876	$ 897
Additions, Charged to Income	1,392	541
Additions, Other Accounts	278	339
Deductions	(1,391)	(901)
Balance at End of Year	$ 1,337	$ 876