Investments (Details 10) (Mortgage Receivables Member, USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Mortgage Receivables Member
Financing Receivable Recorded Investment Aging
Financing Receivable Recorded Investment 30 To 59 Days Past Due	$ 0	$ 0
Financing Receivable Recorded Investment 60 To 89 Days Past Due	4,298	0
Financing Receivable Recorded Investment Equal To Greater Than 90 Days Past Due	13,021	15,555
Total past due	17,319	15,555
Financing Receivable Recorded Investment Current	898,421	876,495
Total mortgage loans	$ 915,740	$ 892,050

Financing receivables that are less than 60 days past due but more than 29 days past due.

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- Definition

Financing receivables that are less than 90 days past due but more than 59 days past due.

+ Details

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Namespace Prefix:	rga
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Details

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Balance Type:	na
Period Type:	duration

- Definition

Financing receivables that are current.

+ Details

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Namespace Prefix:	rga
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ Details

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Namespace Prefix:	rga
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Reflects the sum of the gross carrying amounts of unpaid loans issued to businesses to acquire, develop, construct, improve, or refinance land or a building. Includes [but is not limited to] commercial mortgage loans, which are secured by a [legal] security interest in real property [commercial building or business real property] which thereby serves as collateral securing repayment of the loan; and construction financing, which is an obligation generally in the form of a [promissory] note, used for the funding of construction projects.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Audit and Accounting Guide (AAG)
-Number AAG-DEP
-Chapter 8
-Paragraph 51, 52, 53
-IssueDate 2006-05-01

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 01-6
-Paragraph 13
-Subparagraph e

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 60
-Paragraph 47

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 7
-Subparagraph a
-Article 9

+ Details

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Period Type:	instant