Represents Defined Benefit Plan Termination Benefits, Terminated Participants Minimum Accrued Lump Sum Values.

No definition available.

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- Definition

Employee vesting percentage.

+ References

No definition available.

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- Definition

Defined contribution plan employer contribution as percentage of eligible compensation.

+ References

No definition available.

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- Definition

Health reimbursement account balance.

+ References

No definition available.

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- Definition

Health reimbursement accounts funding.

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No definition available.

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- Definition

Minimum years of service required for full vesting.

+ References

No definition available.

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- Definition

Reduction in expenses due to changes in plan for other postretirement benefits.

+ References

No definition available.

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- Definition

Amount of commitment made to pay deferred cash remuneration.

+ References

No definition available.

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- Definition

The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

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-Topic 710

-SubTopic 10

-Section 30

-Paragraph 1

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- Definition

Minimum period the individual is required to perform services to be fully vested under the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 710

-SubTopic 10

-Section 55

-Paragraph 7

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- Definition

Descriptive information regarding the employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid in the current remaining fiscal period. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions. Description may include a range of expected contributions, required minimum contribution, whether the expected contribution is discretionary, and further explanation.

+ References

No definition available.

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- Definition

Amount included in accumulated other comprehensive income (AOCI) related to gain (loss) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position.

+ References

No definition available.

+ Details

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- Definition

Description of target allocation percentages, or range of percentages, considering the major categories of plan assets as of the latest statement of financial position presented (on a weighted-average basis for employers with more than one plan) that are pertinent to an understanding of the plan investment policies and strategies.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(i)

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

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- Definition

The amount of pension benefit costs recognized during the period for (1) defined benefit plans and (2) defined contribution plans. For defined benefit plans, pension expense includes the following components: service cost, interest cost, expected return on plan assets, gain (loss) on plan assets, prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. For defined contribution plans, the pension expense generally equals the firm's contribution to employees' accounts (if the firm contributes) during the period.

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-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

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Pension Plans and Other Postretirement Benefits (Details Textual) (USD $) In Thousands, unless otherwise specified	12 Months Ended			2 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014	Dec. 31, 2006
Pension Plans and Other Postretirement Benefits (Textual) [Abstract]
Reduction in expense due to changes in the plan for other postretirement benefits	$ 2,980	$ 196	$ 431
Pension Plans and Other Postretirement Benefits (Additional Textual) [Abstract]
Employer Contribution as Percentage of Eligible Compensation	5.00%
Total expense recorded for plans	11,850us-gaap_PensionExpense	10,295us-gaap_PensionExpense	10,415us-gaap_PensionExpense
Health reimbursement account balance	2,485hmn_HealthReimbursementAccountBalance			2,485hmn_HealthReimbursementAccountBalance	7,310hmn_HealthReimbursementAccountBalance
Health reimbursement accounts funding	252hmn_HealthReimbursementAccountsFunding	181hmn_HealthReimbursementAccountsFunding	168hmn_HealthReimbursementAccountsFunding	252hmn_HealthReimbursementAccountsFunding
Total Fixed Maturities [Member]
Pension Plans and Other Postretirement Benefits (Textual) [Abstract]
Defined Benefit Plan, Target Allocation Percentage	50% fixed income funds
Equity Securities [Member]
Pension Plans and Other Postretirement Benefits (Textual) [Abstract]
Defined Benefit Plan, Target Allocation Percentage	50% equity
Defined Benefit Plan [Member]
Pension Plans and Other Postretirement Benefits (Textual) [Abstract]
Expected amortization of net loss expected in the next fiscal year	1,626
Deferred Compensation Arrangement with Individual, Cash Award Granted, Amount	4,200			4,200
Deferred Compensation Arrangement with Individual, Compensation Expense				1,600
Defined Benefit Plan Termination Benefits, Terminated Participants Minimum Accrued Lump Sum Values				100
Supplemental Retirement Plans [Member]
Pension Plans and Other Postretirement Benefits (Textual) [Abstract]
Expected amortization of net loss expected in the next fiscal year	273
401 K [Member]
Pension Plans and Other Postretirement Benefits (Textual) [Abstract]
Employee Vesting Percentage	100.00%
401(k) Plan Employer Contribution Percent	3.00%
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year, Description	In November 2014, the Company communicated that effective January 1, 2015 it would begin matching each dollar of employee contributions up to a 5% maximum — in addition to maintaining the automatic 3% “safe harbor” contribution.
Deferred Compensation Arrangement with Individual, Requisite Service Period	5 years
Pension Costs [Member]
Pension Plans and Other Postretirement Benefits (Textual) [Abstract]
Expected amortization of net loss expected in the next fiscal year	$ 0
Qualified Defined Contribution Plan [Member]
Pension Plans and Other Postretirement Benefits (Textual) [Abstract]
Participants are 100% vested in the Defined Contribution plan after	3 years
Employee Vesting Percentage	100.00%