Fair values of financial assets and liabilities - Valuation techniques - financial liabilities (Details) - GBP (£) £ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2018	Dec. 31, 2017
Disclosure of significant unobservable inputs used in fair value measurement of liabilities [line items]
Financial liabilities, fair value	£ 71,338	£ 77,001
Level 3
Disclosure of significant unobservable inputs used in fair value measurement of liabilities [line items]
Financial liabilities, fair value	782	804
Maximum \| Level 3
Disclosure of significant unobservable inputs used in fair value measurement of liabilities [line items]
Financial liabilities	500	500
Derivative financial instruments
Disclosure of significant unobservable inputs used in fair value measurement of liabilities [line items]
Financial liabilities, fair value	25,561	26,124
Derivative financial instruments \| Level 3
Disclosure of significant unobservable inputs used in fair value measurement of liabilities [line items]
Financial liabilities, fair value	772	804
At fair value through profit or loss
Disclosure of significant unobservable inputs used in fair value measurement of liabilities [line items]
Financial liabilities, fair value	45,777	50,877
At fair value through profit or loss \| Level 3
Disclosure of significant unobservable inputs used in fair value measurement of liabilities [line items]
Financial liabilities, fair value	10
Interest rate derivatives \| Derivative financial instruments \| Option pricing model \| Level 3
Disclosure of significant unobservable inputs used in fair value measurement of liabilities [line items]
Financial liabilities, fair value	£ 772	£ 804
Interest rate derivatives \| Derivative financial instruments \| Option pricing model \| Minimum \| Level 3
Disclosure of significant unobservable inputs used in fair value measurement of liabilities [line items]
Interest rate volatility	10.00%	9.00%
Interest rate derivatives \| Derivative financial instruments \| Option pricing model \| Maximum \| Level 3
Disclosure of significant unobservable inputs used in fair value measurement of liabilities [line items]
Interest rate volatility	89.00%	94.00%

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

No definition available.

+ Details

Name:	ifrs-full_DisclosureOfSignificantUnobservableInputsUsedInFairValueMeasurementOfLiabilitiesLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of liabilities that are: (a) a contractual obligation: (i) to deliver cash or another financial asset to another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially unfavourable to the entity; or (b) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to deliver a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose, rights, options or warrants to acquire a fixed number of the entity’s own equity instruments for a fixed amount of any currency are equity instruments if the entity offers the rights, options or warrants pro rata to all of its existing owners of the same class of its own non-derivative equity instruments. Also, for those purposes the entity’s own equity instruments do not include puttable financial instruments that are classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. As an exception, an instrument that meets the definition of a financial liability is classified as an equity instrument if it has all the features and meets the conditions in paragraphs 16A-16B or paragraphs 16C-16D of IAS 32. [Refer: Financial instruments, class [member]; Financial assets; Financial liabilities; Derivatives [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2016-01-13
-Paragraph 25
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2016-03-30&anchor=para_25&doctype=Standard
-URIDate 2016-03-31

+ Details

Name:	ifrs-full_FinancialLiabilities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fair value of financial liabilities. [Refer: At fair value [member]; Financial liabilities]

+ References

+ Details

Name:	ifrs-full_FinancialLiabilitiesAtFairValue
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Interest rate used as a significant Level 3 unobservable input for liabilities. [Refer: Level 3 of fair value hierarchy [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IFRS
-Number 13
-IssueDate 2016-01-13
-Paragraph B36
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2016-03-30&anchor=para_B36_a&doctype=Appendix&seq=2
-URIDate 2016-03-31

+ Details

Name:	ifrs-full_InterestRateSignificantUnobservableInputsLiabilities
Namespace Prefix:	ifrs-full_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	ifrs-full_LevelsOfFairValueHierarchyAxis=ifrs-full_Level3OfFairValueHierarchyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_RangeAxis=ifrs-full_TopOfRangeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_CategoriesOfFinancialLiabilitiesAxis=lyg_DerivativesDesignatedAsHedgingInstrumentsCategoryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_CategoriesOfFinancialLiabilitiesAxis=ifrs-full_FinancialLiabilitiesAtFairValueThroughProfitOrLossCategoryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_ClassesOfFinancialLiabilitiesAxis=lyg_InterestRateDerivativesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_ValuationTechniquesUsedInFairValueMeasurementAxis=ifrs-full_OptionPricingModelMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_RangeAxis=ifrs-full_BottomOfRangeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: