Mortgage Loans on Real Estate (Troubled Debt Restructurings) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013 loans	Dec. 31, 2012 loans
Financing Receivable, Modifications [Line Items]
Number of TDRs	18	24
Principal balance outstanding	$ 45,653	$ 68,050
Specific loan loss allowance	(6,653)	(10,969)
Net carrying amount	39,000	57,081
East [Member]
Financing Receivable, Modifications [Line Items]
Number of TDRs	1	1
Principal balance outstanding	3,712	4,208
Specific loan loss allowance	(949)	(1,425)
Net carrying amount	2,763	2,783
Mountain [Member]
Financing Receivable, Modifications [Line Items]
Number of TDRs	7	10
Principal balance outstanding	22,140	28,786
Specific loan loss allowance	(329)	(1,702)
Net carrying amount	21,811	27,084
South Atlantic [Member]
Financing Receivable, Modifications [Line Items]
Number of TDRs	7	9
Principal balance outstanding	13,930	23,358
Specific loan loss allowance	(4,177)	(5,047)
Net carrying amount	9,753	18,311
East North Central [Member]
Financing Receivable, Modifications [Line Items]
Number of TDRs	1	1
Principal balance outstanding	2,219	2,232
Specific loan loss allowance	(467)	(467)
Net carrying amount	1,752	1,765
West North Central [Member]
Financing Receivable, Modifications [Line Items]
Number of TDRs	1	3
Principal balance outstanding	1,938	9,466
Specific loan loss allowance	(475)	(2,328)
Net carrying amount	1,463	7,138
West South Central [Member]
Financing Receivable, Modifications [Line Items]
Number of TDRs	1
Principal balance outstanding	1,714
Specific loan loss allowance	(256)
Net carrying amount	$ 1,458

Amount of allowance for credit losses related to receivables which had been measured under a general allowance for credit losses methodology that are now identified as troubled debt restructurings.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 65

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7484272&loc=SL7484277-172609

+ Details

Name:	us-gaap_AllowanceForCreditLossesChangeInMethodOfCalculatingImpairment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_FinancingReceivableModificationsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953676-111524

+ Details

Name:	us-gaap_FinancingReceivableModificationsNumberOfContracts2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

+ Details

Name:	us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

+ Details

Name:	us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration