XML 63 R51.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Employee Benefit Plans (Detail) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2018 | Mar. 31, 2017
Defined Benefit Plan Disclosure [Line Items] |  |  |
Amortization of prior service cost |  | $ (19) | $ (19)
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) |  | (237) | (276)
Chesapeake Postretirement Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Interest cost |  | 10 | 10
Amortization of prior service cost |  | (19) | (19)
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) |  | (15) | (16)
Net periodic cost (benefit) | [1] | 6 | 7
Total periodic cost |  | 6 | 7
Florida Public Utilities Company Medical Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Interest cost |  | 12 | 13
Net periodic cost (benefit) | [1] | 12 | 13
Amortization of pre-merger regulatory asset |  | 2 | 2
Total periodic cost |  | 14 | 15
Florida Public Utilities Company Pension Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Interest cost |  | 592 | 623
Expected return on plan assets |  | (774) | (699)
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) |  | (109) | (131)
Net periodic cost (benefit) | [1] | (73) | 55
Amortization of pre-merger regulatory asset |  | 191 | 191
Total periodic cost |  | 118 | 246
Chesapeake Pension SERP [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Interest cost |  | 21 | 22
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) |  | (25) | (22)
Net periodic cost (benefit) | [1] | 46 | 44
Total periodic cost |  | 46 | 44
Chesapeake Pension Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Interest cost |  | 97 | 103
Expected return on plan assets |  | (138) | (127)
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) |  | (88) | (107)
Net periodic cost (benefit) | [1] | 47 | 83
Total periodic cost |  | $ 47 | $ 83
[1] | See Note 8, Stockholder's Equity.

X
- Definition Amortization of pre-merger regulatory asset. + References No definition available. + Details
Name: | cpk_AmortizationOfPreMergerRegulatoryAsset
Namespace Prefix: | cpk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Periodic Cost Benefit + References No definition available. + Details
Name: | cpk_PeriodicCostBenefit
Namespace Prefix: | cpk_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanActuarialGainLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(5) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_DefinedBenefitPlanDisclosureLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(3) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of cost recognized for passage of time related to defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(2) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanInterestCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_RetirementPlanNameAxis=cpk_ChesapeakePostretirementPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanNameAxis=cpk_FloridaPublicUtilitiesCompanyMedicalPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanNameAxis=cpk_FloridaPublicUtilitiesCompanyPensionPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanNameAxis=cpk_ChesapeakePensionSerpMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanNameAxis=cpk_ChesapeakePensionPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |