Name:	grfs_IncreaseInInvestmentsAccountedForUsingEquityMethodThroughTransferAccountedForInvesteesWithSimilarActivityToThatOfGroup
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Period Type:	duration

Investment accounted for using equity method adjusted for transfer accounted for investees with similar activity to that of Group.

No definition available.

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Data Type:	xbrli:monetaryItemType
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- References

No definition available.

Name:	grfs_MovementInInvestmentAccountedForUsingEquityMethodAbstract
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The amount reclassified out of the investment accounted for using equity method category.

No definition available.

Name:	grfs_ReclassificationOutOfInvestmentAccountedForUsingEquityMethod
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Data Type:	xbrli:monetaryItemType
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The entity's share of the profit (loss) of associates and joint ventures accounted for using the equity method, excluding impairment loss.

No definition available.

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Data Type:	xbrli:monetaryItemType
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The amount of dividends received.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2019-01-01
-Paragraph B12
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2019-en-r&anchor=para_B12_a&doctype=Appendix&subtype=B
-URIDate 2019-03-27

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Period Type:	duration

The amount of investments accounted for using the equity method. The equity method is a method of accounting whereby the investment is initially recognised at cost and adjusted thereafter for the post-acquisition change in the investor's share of net assets of the investee. The investor's profit or loss includes its share of the profit or loss of the investee. The investor's other comprehensive income includes its share of the other comprehensive income of the investee. [Refer: At cost [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2019-01-01
-Paragraph 24
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2019-en-r&anchor=para_24_a&doctype=Standard
-URIDate 2019-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2019-01-01
-Paragraph B16
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2019-en-r&anchor=para_B16&doctype=Appendix&subtype=B
-URIDate 2019-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 54
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_54_e&doctype=Standard
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The entity's share of the other comprehensive income of associates and joint ventures accounted for using the equity method, net of tax. [Refer: Associates [member]; Investments accounted for using equity method; Joint ventures [member]; Other comprehensive income]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective on first application of IFRS 9
-Name IFRS
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-IssueDate 2019-01-01
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-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=4&code=ifrs-tx-2019-en-b&anchor=para_39M_b&doctype=Standard
-URIDate 2019-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2019-01-01
-Paragraph B16
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2019-en-r&anchor=para_B16_c&doctype=Appendix&subtype=B
-URIDate 2019-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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-Paragraph 91
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_91_a&doctype=Standard
-URIDate 2019-03-27