Collateral Obtained Percent Of Fair Value Reverse Repurchase Agreements

No definition available.

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- Definition

Funds Withheld At Interest concentrated with one client.

+ References

No definition available.

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- Definition

Funds Withheld At Interest As A Percentage Of Total Investments

+ References

No definition available.

+ Details

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- References

No definition available.

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- Definition

The required minimum percentage fair value collateral balance that the Company must maintain of the cash received in repurchase programs in which securities are pledged to a third party.

+ References

No definition available.

+ Details

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- Definition

Mortgage Loans as a Percent Of total Cash And Invested Assets

+ References

No definition available.

+ Details

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- Definition

The maximum loan-to-value ratio at the time of mortgage loan approval.

+ References

No definition available.

+ Details

Name:	rga_MortgageLoanToValueRatioOnApproval
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- Definition

The amount represents the total percentage of each property type in comparison to the total of mortgage loans whose balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

+ References

No definition available.

+ Details

Name:	rga_MortgageLoansOnRealEstateCommercialAndConsumerNetPercentageOfTotal
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- Definition

Other Invested Assets as a Percent Of total Cash And Invested Assets

+ References

No definition available.

+ Details

Name:	rga_OtherInvestedAssetsPercentOfCashAndInvestedAssets
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- Definition

Policy Loans as a percentage of total investments.

+ References

No definition available.

+ Details

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- Definition

The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

+ References

No definition available.

+ Details

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- Definition

Securities as percentage of consolidated stockholder equity.

+ References

No definition available.

+ Details

Name:	rga_SecuritiesAsPercentageOfConsolidatedStockholderEquity
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- Definition

Securities Borrowed Or Pledged, Minimum Fair Value Percentage

+ References

No definition available.

+ Details

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- Definition

Amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(m)(1)(i)(A)(ii))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph m

-Subparagraph 1

-Article 4

+ Details

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- Definition

This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (b)(3)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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- Definition

Financing receivables that are equal to or greater than 90 days past due.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953401-111524

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- Definition

Amount of the reinsurer's funds held on its behalf by the ceding insurer, including funds held in trust, under reinsurance treaties or contracts with the assuming insurer as security for the payment of the obligations thereunder.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.2,10)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 2, 10

-Article 7

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27340-111563

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- Definition

Fair value of securities pledged as collateral against securities sold under agreement to repurchase.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226013-175313

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Investments (Narrative) (Details) $ in Thousands	3 Months Ended		6 Months Ended
Investments (Narrative) (Details) $ in Thousands	Jun. 30, 2015 USD ($) securities	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) securities	Jun. 30, 2014 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($) securities	Mar. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Investment Narrative [Line Items]
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Credit Losses on Debt Securities Held	$ 7,284	$ 7,284	$ 7,284	$ 7,284	$ 7,284	$ 7,284	$ 11,696	$ 11,696
Policy Loans Percent Of Total Investments	3.60%		3.60%			3.50%
Mortgage Loan To Value Ratio on Approval			75.00%
Mortgage Loan Percent Of Cash And Invested Assets	7.80%		7.80%			7.40%
Proceeds From Sale Of Available For Sale Securities Sold At Loss	$ 651,300	222,800	$ 850,900	457,900
Available-for-sale Securities, Gross Realized Losses	$ 14,475	$ 6,877	$ 28,071	$ 13,460
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions \| securities	1,566		1,566			932
Securities As Percentage Of Consolidated Stockholder Equity	10.00%		10.00%
Securities Borrowed Or Pledged, Minimum Fair Value Percentage			100.00%
Minimum Collateral Balance of Cash Received Fair Value			105.00%
Collateral Obtained Percent Of Fair Value Reverse Repurchase Agreements			100.00%
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	100.00%		100.00%			100.00%
Funds Withheld At Interest Percent Of Total Investments	14.70%		14.70%			16.10%
Funds withheld at interest	$ 5,840,076		$ 5,840,076			$ 5,922,561
Funds Held Under Reinsurance Agreements Asset Specific Client	$ 4,200,000		$ 4,200,000
Other Invested Assets Percent Of Cash And Invested Assets	2.80%		2.80%			3.30%
Assets Sold under Agreements to Repurchase, Repurchase Liability						$ 101,400
Securities Sold under Agreements to Repurchase, Fair Value of Collateral	$ 0		$ 0			107,158
Investment in mortgage loans
Investment Narrative [Line Items]
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	$ 0		$ 0			$ 0
CALIFORNIA
Investment Narrative [Line Items]
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	20.60%		20.60%			18.70%