Represents a sale (new stock issuance) by a subsidiary to noncontrolling interests (third parties, parties directly or indirectly unrelated to parent) during the period. The capital transaction by subsidiary does not result in a loss of control by the parent, but does effect a change in total (consolidated) equity attributable to the parent.

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- Definition

Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
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-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=96868048&loc=SL4616395-111683

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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- Definition

Amount of increase in noncontrolling interest from subsidiary issuance of equity interests to noncontrolling interest holders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=96868048&loc=SL4569655-111683

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- Definition

The cash outflow associated with the acquisition of or advances to an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, and joint venture or equity method investment) or the acquisition of an additional interest in a subsidiary (controlled entity).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (d)
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Subsequent Events (Details) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
Subsequent Events (Details) - USD ($) $ in Thousands	Jan. 01, 2018	Feb. 02, 2018	Dec. 31, 2017	Dec. 31, 2016
Upsilon RFO Re Ltd. \| Primary Beneficiary \| Non-voting preference shares
Subsequent Event [Line Items]
Non-voting preference shares issued to third parties			$ 180,600	$ 166,600
Investment in variable interest entity			$ 27,200	$ 55,200
Upsilon RFO Re Ltd. \| Primary Beneficiary \| RenaissanceRe Holdings Ltd.
Subsequent Event [Line Items]
Variable interest entity, ownership percentage			20.80%	28.80%
RenaissanceRe Medici Fund Ltd.
Subsequent Event [Line Items]
Noncontrolling interest, value subscribed			$ 149,182	$ 79,518
Redemption of shares from redeemable noncontrolling interests			$ 48,049	$ 21,729
Redeemable noncontrolling interest, ownership percentage			26.80%	36.50%
Subsequent Event \| Upsilon RFO Re Ltd. \| Primary Beneficiary
Subsequent Event [Line Items]
Variable interest entity, ownership percentage	14.10%
Subsequent Event \| Upsilon RFO Re Ltd. \| Primary Beneficiary \| Non-voting preference shares
Subsequent Event [Line Items]
Non-voting preference shares issued to third parties	$ 600,500
Investment in variable interest entity	$ 75,000
Subsequent Event \| RenaissanceRe Medici Fund Ltd.
Subsequent Event [Line Items]
Redeemable noncontrolling interest, ownership percentage		17.80%
Subsequent Event \| RenaissanceRe Medici Fund Ltd. \| Third-party investor
Subsequent Event [Line Items]
Noncontrolling interest, value subscribed		$ 81,000
Subsequent Event \| RenaissanceRe Medici Fund Ltd. \| RenaissanceRe Holdings Ltd.
Subsequent Event [Line Items]
Redemption of shares from redeemable noncontrolling interests		$ 25,000