Investments - Additional Information (Detail) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of investments in financial assets and real estate [line items]
Current financial assets	€ 14,654	€ 13,287
Percentage of properties appraised	100.00%	99.00%
Percentage of properties appraised performed by independent external appraisers	99.00%	98.00%
Investments in real estate	€ 2,901	€ 2,700	€ 2,147
Rental income	83	82	71
Direct operating expense from investment property generating rental income	59	63	71
Direct operating expense from investment property not generating rental income	2	2	€ 1
Aegon Americas [member]
Disclosure of investments in financial assets and real estate [line items]
Investments in real estate	€ 653	530
Remaining lease terms of non-cancellable leases	up to 20 years
Aegon Netherlands [member]
Disclosure of investments in financial assets and real estate [line items]
Investments in real estate	€ 2,229	€ 2,150

The disclosure of line items(s) of investments in financial assets and real estate.

No definition available.

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- Definition

Non-cancellable lease remaining lease term.

+ References

No definition available.

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- Definition

Percentage of value of properties for general account and account of policyholders appraised.

+ References

No definition available.

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- Definition

Percentage of appraised properties performed by independent external appraisers

+ References

No definition available.

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- Definition

The amount of current financial assets. [Refer: Financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2019-01-01
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- Definition

The amount of direct operating expenses (including repairs and maintenance) arising from investment property that generated rental income during the period recognised in profit or loss. [Refer: Investment property]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 40
-IssueDate 2019-01-01
-Paragraph 75
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- Definition

The amount of direct operating expenses (including repairs and maintenance) arising from investment property that did not generate rental income during the period recognised in profit or loss. [Refer: Investment property]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of property (land or a building - or part of a building - or both) held (by the owner or by the lessee as a right-of-use asset) to earn rentals or for capital appreciation or both, rather than for: (a) use in the production or supply of goods or services or for administrative purposes; or (b) sale in the ordinary course of business.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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- Definition

The amount of rental income arising from investment property recognised in profit or loss. [Refer: Investment property]

+ References

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