Health Care Cost Trend Rate Used to Measure the Accumulated Postretirement Benefit Obligation (Details) (USD $)	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Defined benefit plan, ultimate health care cost trend rate	4.50%	4.50%
Defined benefit plan, year that rate reaches ultimate trend rate	2029	2029
Defined benefit plan, health care cost trend rate assumed for next fiscal year	7.30%	7.60%
Defined Benefit Plan, Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates [Abstract]
Defined benefit plan, effect of one percentage point increase on accumulated postretirement benefit obligation	$ 265,390
Defined benefit plan, effect of one percentage point increase on service and interest cost components	31,993
Defined benefit plan, effect of one percentage point decrease on accumulated postretirement benefit obligation	300,327
Defined benefit plan, effect of one percentage point decrease on service and interest cost components	$ 36,715

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

+ Details

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Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

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+ Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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+ Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

+ Details

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- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ 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 (l)

-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Health Care Cost Trend Rate

-URI http://asc.fasb.org/extlink&oid=6514820

+ Details

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- Definition

The ultimate trend rate for health care costs.

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+ Details

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- Definition

Year the ultimate health care cost trend rate is expected to be reached, in CCYY format.

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+ Details

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