Impaired Mortgage Loans.

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- Definition

This represents the recorded investment for impaired mortgage loans held-for-investment.

+ Details

Name:	met_RecordedInvestmentForImpairedMortgageLoansHeldForInvestment
Namespace Prefix:	met
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This represents the unpaid principal balance for impaired mortgage loans held-for-investment.

+ Details

Name:	met_UnpaidPrincipalBalanceForImpairedMortgageLoansHeldForInvestment
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 60
-Paragraph 47

+ Details

Name:	us-gaap_AllowanceForLoanAndLeaseLossesRealEstate
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Reflects the adjusted carrying amount of loans for which it is probable, based on current facts and circumstances, that a creditor will not initially be able to collect all amounts due according to the contractual terms of the loan agreement, or will not recover the previously reported carrying amount of the loan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 114
-Paragraph 20
-Subparagraph a

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher OTS
-Name Federal Regulation (FR)
-Number Title 12
-Chapter V
-Section 563c.102
-Paragraph 8
-Subparagraph j(ii)
-Subsection I

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Reflects the carrying amount of loans which have been written down and for which there is a related reserve for credit loss.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Reflects the carrying amount of loans which have been written down and for which there is no related reserve for credit loss.

+ References

+ Details

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Balance Type:	debit
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Investments (Details 36) (USD $) In Millions	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2009
Impaired Mortgage Loans
Unpaid Principal Balance	$ 493		$ 507
Valuation allowances	566	621	664	734	751	721
Carrying value	403		403
Loans with a Valuation Allowance [Member] \| Commercial mortgage loans portfolio segment [Member]
Impaired Mortgage Loans
Unpaid Principal Balance	126		120
Recorded Investment	126		120
Valuation allowances	28		36
Carrying value	98		84
Loans without a Valuation Allowance [Member] \| Commercial mortgage loans portfolio segment [Member]
Impaired Mortgage Loans
Unpaid Principal Balance	105		99
Recorded Investment	95		87
Specific credit losses [Member] \| Commercial mortgage loans portfolio segment [Member]
Impaired Mortgage Loans
Valuation allowances	28		36
Non-specifically identified credit losses [Member] \| Commercial mortgage loans portfolio segment [Member]
Impaired Mortgage Loans
Valuation allowances	441		526
Commercial mortgage loans portfolio segment [Member]
Impaired Mortgage Loans
Unpaid Principal Balance	231		219
Valuation allowances	469	532	562	621	624	589
Carrying value	193		171
Loans with a Valuation Allowance [Member] \| Agricultural mortgage loans portfolio segment [Member]
Impaired Mortgage Loans
Unpaid Principal Balance	131		146
Recorded Investment	128		146
Valuation allowances	43		52
Carrying value	85		94
Loans without a Valuation Allowance [Member] \| Agricultural mortgage loans portfolio segment [Member]
Impaired Mortgage Loans
Unpaid Principal Balance	105		123
Recorded Investment	100		119
Specific credit losses [Member] \| Agricultural mortgage loans portfolio segment [Member]
Impaired Mortgage Loans
Valuation allowances	43		52
Non-specifically identified credit losses [Member] \| Agricultural mortgage loans portfolio segment [Member]
Impaired Mortgage Loans
Valuation allowances	36		36
Agricultural mortgage loans portfolio segment [Member]
Impaired Mortgage Loans
Unpaid Principal Balance	236		269
Valuation allowances	79	76	88	96	110	115
Carrying value	185		213
Loans with a Valuation Allowance [Member] \| Residential mortgage loans portfolio segment [Member]
Impaired Mortgage Loans
Unpaid Principal Balance	11		3
Recorded Investment	11		3
Valuation allowances	1		0
Carrying value	10		3
Loans without a Valuation Allowance [Member] \| Residential mortgage loans portfolio segment [Member]
Impaired Mortgage Loans
Unpaid Principal Balance	15		16
Recorded Investment	15		16
Specific credit losses [Member] \| Residential mortgage loans portfolio segment [Member]
Impaired Mortgage Loans
Valuation allowances	1		0
Non-specifically identified credit losses [Member] \| Residential mortgage loans portfolio segment [Member]
Impaired Mortgage Loans
Valuation allowances	17		14
Residential mortgage loans portfolio segment [Member]
Impaired Mortgage Loans
Unpaid Principal Balance	26		19
Valuation allowances	18	13	14	17	17	17
Carrying value	25		19
Loans with a Valuation Allowance [Member]
Impaired Mortgage Loans
Unpaid Principal Balance	268		269
Recorded Investment	265		269
Carrying value	193		181
Loans without a Valuation Allowance [Member]
Impaired Mortgage Loans
Unpaid Principal Balance	225		238
Recorded Investment	210		222
Specific credit losses [Member]
Impaired Mortgage Loans
Valuation allowances	72		88
Non-specifically identified credit losses [Member]
Impaired Mortgage Loans
Valuation allowances	$ 494		$ 576