XML 23 R33.htm IDEA: XBRL DOCUMENT v2.4.1.9

Rate and Regulatory Matters (Schedule of Regulatory Assets) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Regulatory Assets [Line Items]
Regulatory Assets	$ 66,216us-gaap_RegulatoryAssets	$ 34,386us-gaap_RegulatoryAssets
Retirement Benefits [Member]
Regulatory Assets [Line Items]
Regulatory Assets	47,868us-gaap_RegulatoryAssets / us-gaap_RegulatoryAssetAxis = us-gaap_PensionCostsMember	20,826us-gaap_RegulatoryAssets / us-gaap_RegulatoryAssetAxis = us-gaap_PensionCostsMember
Remaining recovery period	Various
Income Taxes [Member]
Regulatory Assets [Line Items]
Regulatory Assets	17,195us-gaap_RegulatoryAssets / us-gaap_RegulatoryAssetAxis = msex_IncomeTaxesMember	12,207us-gaap_RegulatoryAssets / us-gaap_RegulatoryAssetAxis = msex_IncomeTaxesMember
Remaining recovery period	Various
Rate Cases, Tank Painting, and Other [Member]
Regulatory Assets [Line Items]
Regulatory Assets	$ 1,153us-gaap_RegulatoryAssets / us-gaap_RegulatoryAssetAxis = msex_RateCasesStormCostsTankPaintingOtherMember	$ 1,353us-gaap_RegulatoryAssets / us-gaap_RegulatoryAssetAxis = msex_RateCasesStormCostsTankPaintingOtherMember
Remaining recovery period	2-9 years

X

- Definition

The period remaining for recovery of costs in the rates we charge customers.

+ References

No definition available.

+ Details

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- Details

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Period Type:	duration

X

- Definition

The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 340

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

+ Details

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- Details

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- Details

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