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SUBSEQUENT EVENTS (Details)	Jul. 29, 2021 EUR (€) credit_facility	Jun. 30, 2021 EUR (€)	Dec. 31, 2020 EUR (€)	Dec. 31, 2019 EUR (€)
Disclosure of non-adjusting events after reporting period [line items]
Amount drawn under credit facility		€ 2,257,000,000	€ 2,391,000,000	€ 2,361,000,000
Expiration of Credit Facilities | Secured and Unsecured German Credit Facilities due 2022 | German State
Disclosure of non-adjusting events after reporting period [line items]
Number of credit facilities | credit_facility	2
Amount drawn under credit facility	€ 0

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- Definition

Number Of Credit Facilities

+ References

No definition available.

+ Details

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- Definition

The amount of outstanding funds that the entity is obligated to repay.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_55&doctype=Standard
-URIDate 2020-01-01

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- Definition

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.

+ References

No definition available.

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- Details

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