Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=49168827

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The increase in the fair value of plan assets from contributions made by the employer.

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount of employer's best estimate of contributions expected to be paid to the plan in the current remaining fiscal period.

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No definition available.

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Amount of discretionary contributions made by an employer to a defined contribution plan.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The shares that, although not legally released, will be released by a future scheduled and committed debt service payment and will be allocated to employees for service rendered in the current accounting period. The ESOP documents typically define the period of service to which the shares relate. ESOP shares are released to compensate employees directly, to settle employer liabilities for other employee benefits, and to replace dividends on allocated shares that are used for debt service.

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This item represents the number of shares provided to the Employee Stock Ownership Plan (ESOP) during the period.

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Sum of the allocated, committed-to-be-released and suspense shares of the entity held by the plan.

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Employee Benefits (Details) - USD ($) $ in Thousands		3 Months Ended
Employee Benefits (Details) - USD ($) $ in Thousands	Oct. 30, 2015	Mar. 31, 2016	Mar. 31, 2015
Employee Stock Ownership Plan and Trust (ESOP) [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Additional shares contributed to ESOP (in shares)		59,200
Shares released from trust (in shares)		59,200
Total remaining balance of shares in the ESOP (in shares)		200
Postretirement Benefits [Member]
Net Periodic benefit costs related to retirement plans [Abstract]
Service cost		$ 0	$ 0
Interest cost		3	7
Amortization of prior service cost		(13)	(29)
Actuarial net loss		275	434
Net periodic benefit cost		265	412
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]
Contributions by employer on behalf of employees		300
Estimated future employer contributions in current fiscal year		2,600
Supplemental Executive Retirement Plan [Member]
Net Periodic benefit costs related to retirement plans [Abstract]
Net periodic benefit cost			$ 200
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]
Contributions by employer on behalf of employees	$ 7,600
Employer discretionary contribution amount		$ 300