The sum of insurance premiums earned, premiums earned on the income statement for all insurance contracts after subtracting any amounts ceded to another insurer and adding premiums assumed from other insurers, plus contract charges earned on investment and universal life-type contracts.

No definition available.

+ Details

Name:	hmn_InsurancePremiumsAndContractChargesEarned
Namespace Prefix:	hmn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

Name:	us-gaap_Assets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669619-108580

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(22))
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669625-108580

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(18))
-URI http://asc.fasb.org/extlink&oid=114873790&loc=SL114874131-224263

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(20))
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

+ Details

Name:	us-gaap_NetIncomeLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(2))
-URI http://asc.fasb.org/extlink&oid=114873790&loc=SL114874131-224263

+ Details

Name:	us-gaap_NetInvestmentIncome
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

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

- Details

Name:	srt_ConsolidationItemsAxis=us-gaap_IntersegmentEliminationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=us-gaap_PropertyLiabilityAndCasualtyInsuranceSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=us-gaap_VariableAnnuityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=us-gaap_LifeInsuranceSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=us-gaap_CorporateAndOtherMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ConsolidationItemsAxis=us-gaap_CorporateNonSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Segment Information - Summarized Financial Information by Segment (Details) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Summarized financial information for these segments
Insurance premiums and contract charges earned													$ 817,333	$ 794,703	$ 759,146
Net investment income													376,507	373,630	361,186
Net income (loss)	$ (20,257)	$ 12,528	$ 5,917	$ 20,155	$ 125,329	$ 26,551	$ 2,261	$ 15,318	$ 19,823	$ 26,923	$ 11,866	$ 25,153	18,343	169,459	83,765
Assets	11,031,896				11,198,340				10,576,824				11,031,896	11,198,340	10,576,824
Intersegment eliminations
Summarized financial information for these segments
Net investment income													(772)	(815)	(855)
Assets	(41,800)				(42,482)				(36,786)				(41,800)	(42,482)	(36,786)
Property and Casualty
Summarized financial information for these segments
Net income (loss)													(14,243)	17,790	25,644
Property and Casualty \| Operating Segments
Summarized financial information for these segments
Insurance premiums and contract charges earned													665,734	648,263	620,514
Net investment income													40,104	36,178	38,998
Assets	1,236,362				1,217,394				1,110,958				1,236,362	1,217,394	1,110,958
Retirement
Summarized financial information for these segments
Net income (loss)													41,736	88,473	50,674
Retirement \| Operating Segments
Summarized financial information for these segments
Insurance premiums and contract charges earned													31,269	28,003	24,937
Net investment income													262,634	261,994	249,410
Assets	7,866,969				8,063,912				7,449,777				7,866,969	8,063,912	7,449,777
Life
Summarized financial information for these segments
Net income (loss)													18,754	77,595	16,559
Life \| Operating Segments
Summarized financial information for these segments
Insurance premiums and contract charges earned													120,330	118,437	113,695
Net investment income													74,399	76,195	73,567
Assets	1,821,351				1,815,732				1,912,771				1,821,351	1,815,732	1,912,771
Corporate and Other \| Corporate and Other
Summarized financial information for these segments
Net investment income													142	78	66
Net income (loss)													(27,904)	(14,399)	(9,112)
Assets	$ 149,014				$ 143,784				$ 140,104				$ 149,014	$ 143,784	$ 140,104