XML 48 R6.htm IDEA: XBRL DOCUMENT
v2.4.1.9

CONSOLIDATED STATEMENTS OF CAPITAL STOCK AND LONG-TERM DEBT (USD $) In Thousands, unless otherwise specified | Dec. 31, 2014 | Dec. 31, 2013
--- | --- | ---
Common Stock, No Par Value | $ 148,668 us-gaap_CommonStockValue | $ 146,185 us-gaap_CommonStockValue
Retained Earnings | 48,623 us-gaap_RetainedEarningsAccumulatedDeficit | 42,560 us-gaap_RetainedEarningsAccumulatedDeficit
TOTAL COMMON EQUITY | 197,291 msex_TotalCommonEquity | 188,745 msex_TotalCommonEquity
TOTAL PREFERRED STOCK | 2,436 us-gaap_PreferredStockValue | 2,886 us-gaap_PreferredStockValue
SUBTOTAL LONG-TERM DEBT | 140,029 us-gaap_LongTermDebt | 133,112 us-gaap_LongTermDebt
Add: Premium on Issuance of Long-term Debt | 1,920 us-gaap_DebtInstrumentUnamortizedPremium | 2,072 us-gaap_DebtInstrumentUnamortizedPremium
Less: Current Portion of Long-term Debt | (5,910)us-gaap_LongTermDebtCurrent | (5,386)us-gaap_LongTermDebtCurrent
TOTAL LONG-TERM DEBT | 136,039 us-gaap_LongTermDebtNoncurrent | 129,798 us-gaap_LongTermDebtNoncurrent
Amortizing Secured Note, due December 20, 2021 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 1,825 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = us-gaap_SecuredDebtMember | 2,005 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = us-gaap_SecuredDebtMember
Amortizing Secured Note, due May 19, 2028 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 5,635 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_SecuredDebt1Member | 6,055 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_SecuredDebt1Member
Amortizing Secured Note, due August 25, 2030 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 4,387 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_SecuredDebt2Member | 4,667 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_SecuredDebt2Member
Amortizing Secured Note, due September 19, 2031 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 4,667 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_SecuredDebt3Member | 4,947 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_SecuredDebt3Member
State Revolving Trust Note, due December 31, 2022 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 421 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNoteMember | 465 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNoteMember
State Revolving Trust Note, due May 1, 2025 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 2,463 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote1Member | 2,654 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote1Member
State Revolving Trust Note, due March 1, 2026 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 506 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote9Member | 541 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote9Member
State Revolving Trust Note, due January 25, 2027 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 536 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote2Member | 569 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote2Member
State Revolving Trust Note, due December 1, 2026 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 697 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote3Member | 742 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote3Member
State Revolving Trust Bond 4.00% to 5.00%, due August 1, 2021 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 299 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustBondMember | 343 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustBondMember
State Revolving Trust Bond 0.00%, due August 1, 2021 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 241 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustBond1Member | 281 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustBond1Member
State Revolving Trust Note, due July 1, 2028 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 313 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote4Member | 330 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote4Member
State Revolving Trust Note, due January 1, 2028 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 104 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote5Member | 110 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote5Member
State Revolving Trust Note, due August 1, 2031 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 1,115 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote6Member | 467 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote6Member
Amortizing Secured Note, due April 20, 2029 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 4,999 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_SecuredDebt4Member | 5,348 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_SecuredDebt4Member
Amortizing Secured Note 7.05%, due January 20, 2030 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 3,771 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_SecuredDebt5Member | 4,021 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_SecuredDebt5Member
Amortizing Secured Note 5.69%, due January 20, 2030 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 7,735 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_SecuredDebt6Member | 8,248 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_SecuredDebt6Member
Amortizing Secured Note, due April 20, 2040 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 8,000 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_SecuredDebt7Member |
State Revolving Trust Note, due July 1, 2031 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 2,411 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote7Member | 2,515 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote7Member
State Revolving Trust Note, due November 30, 2030 [Member] |  |
SUBTOTAL LONG-TERM DEBT | 1,276 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote8Member | 1,333 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_StateRevolvingTrustNote8Member
First Mortgage Bonds - Series X [Member] |  |
SUBTOTAL LONG-TERM DEBT | 215 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage1Member | 268 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage1Member
First Mortgage Bonds - Series Y [Member] |  |
SUBTOTAL LONG-TERM DEBT | 245 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage2Member | 300 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage2Member
First Mortgage Bonds - Series Z [Member] |  |
SUBTOTAL LONG-TERM DEBT | 559 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage3Member | 671 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage3Member
First Mortgage Bonds - Series AA [Member] |  |
SUBTOTAL LONG-TERM DEBT | 700 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage4Member | 830 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage4Member
First Mortgage Bonds - Series BB [Member] |  |
SUBTOTAL LONG-TERM DEBT | 845 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage5Member | 965 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage5Member
First Mortgage Bonds - Series CC [Member] |  |
SUBTOTAL LONG-TERM DEBT | 1,025 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage6Member | 1,145 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage6Member
First Mortgage Bonds - Series EE [Member] |  |
SUBTOTAL LONG-TERM DEBT | 3,550 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage8Member | 3,968 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage8Member
First Mortgage Bonds - Series FF [Member] |  |
SUBTOTAL LONG-TERM DEBT | 4,900 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage9Member | 5,335 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage9Member
First Mortgage Bonds - Series GG [Member] |  |
SUBTOTAL LONG-TERM DEBT | 1,083 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage10Member | 1,171 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage10Member
First Mortgage Bonds - Series HH [Member] |  |
SUBTOTAL LONG-TERM DEBT | 1,390 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage11Member | 1,475 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage11Member
First Mortgage Bonds - Series II [Member] |  |
SUBTOTAL LONG-TERM DEBT | 881 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage12Member | 971 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage12Member
First Mortgage Bonds - Series JJ [Member] |  |
SUBTOTAL LONG-TERM DEBT | 1,090 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage13Member | 1,165 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage13Member
First Mortgage Bonds - Series KK [Member] |  |
SUBTOTAL LONG-TERM DEBT | 1,255 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage14Member | 1,346 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage14Member
First Mortgage Bonds - Series LL [Member] |  |
SUBTOTAL LONG-TERM DEBT | 1,435 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage15Member | 1,505 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage15Member
First Mortgage Bonds - Series MM [Member] |  |
SUBTOTAL LONG-TERM DEBT | 1,537 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage16Member | 1,637 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage16Member
First Mortgage Bonds - Series NN [Member] |  |
SUBTOTAL LONG-TERM DEBT | 1,755 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage17Member | 1,835 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage17Member
First Mortgage Bonds - Series OO [Member] |  |
SUBTOTAL LONG-TERM DEBT | 2,559 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage18Member | 2,709 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage18Member
First Mortgage Bonds - Series PP [Member] |  |
SUBTOTAL LONG-TERM DEBT | 850 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage19Member | 885 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage19Member
First Mortgage Bonds - Series QQ [Member] |  |
SUBTOTAL LONG-TERM DEBT | 9,915 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage20Member | 9,915 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage20Member
First Mortgage Bonds - Series RR [Member] |  |
SUBTOTAL LONG-TERM DEBT | 22,500 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage21Member | 22,500 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage21Member
First Mortgage Bonds - Series SS [Member] |  |
SUBTOTAL LONG-TERM DEBT | 23,000 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage22Member | 23,000 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage22Member
First Mortgage Bonds - Series TT [Member] |  |
SUBTOTAL LONG-TERM DEBT | 2,709 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage23Member | 2,860 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage23Member
First Mortgage Bonds - Series UU [Member] |  |
SUBTOTAL LONG-TERM DEBT | 975 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage24Member | 1,015 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage24Member
First Mortgage Bonds - Series VV [Member] |  |
SUBTOTAL LONG-TERM DEBT | 2,720 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage25Member |
First Mortgage Bonds - Series WW [Member] |  |
SUBTOTAL LONG-TERM DEBT | 935 us-gaap_LongTermDebt / us-gaap_DebtInstrumentAxis = msex_FirstMortgage26Member |
Convertible Preferred Stock $7.00 Series |  |
TOTAL PREFERRED STOCK | 1,007 us-gaap_PreferredStockValue / us-gaap_StatementClassOfStockAxis = us-gaap_ConvertiblePreferredStockMember | 1,457 us-gaap_PreferredStockValue / us-gaap_StatementClassOfStockAxis = us-gaap_ConvertiblePreferredStockMember
Convertible Preferred Stock $8.00 Series [Member] |  |
TOTAL PREFERRED STOCK | 349 us-gaap_PreferredStockValue / us-gaap_StatementClassOfStockAxis = msex_ConvertiblePreferredStock1Member | 349 us-gaap_PreferredStockValue / us-gaap_StatementClassOfStockAxis = msex_ConvertiblePreferredStock1Member
Nonredeemable Preferred Stock $7.00 Series |  |
TOTAL PREFERRED STOCK | 80 us-gaap_PreferredStockValue / us-gaap_StatementClassOfStockAxis = us-gaap_NonredeemablePreferredStockMember | 80 us-gaap_PreferredStockValue / us-gaap_StatementClassOfStockAxis = us-gaap_NonredeemablePreferredStockMember
Nonredeemable Preferred Stock $4.75 Series [Member] |  |
TOTAL PREFERRED STOCK | $ 1,000 us-gaap_PreferredStockValue / us-gaap_StatementClassOfStockAxis = msex_NonredeemablePreferredStock1Member | $ 1,000 us-gaap_PreferredStockValue / us-gaap_StatementClassOfStockAxis = msex_NonredeemablePreferredStock1Member

X
- Definition Refers to total equity attributable to common stockholders. + References No definition available. + Details
Name: | msex_TotalCommonEquity
Namespace Prefix: | msex_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 30 -Article 5 + Details
Name: | us-gaap_CommonStockValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of debt premium that was originally recognized at the issuance of the instrument that has yet to be amortized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400 + Details
Name: | us-gaap_DebtInstrumentUnamortizedPremium
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
Name: | us-gaap_LongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19,20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Article 5 + Details
Name: | us-gaap_LongTermDebtCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 + Details
Name: | us-gaap_LongTermDebtNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Aggregate par or stated value of issued nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable preferred shares, par value and other disclosure concepts are in another section within stockholders' equity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.28) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29 -Article 5 + Details
Name: | us-gaap_PreferredStockValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The cumulative amount of the reporting entity's undistributed earnings or deficit. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 31 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.31(a)(3)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_RetainedEarningsAccumulatedDeficit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage10Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage11Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage12Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage13Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage14Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage15Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage16Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage17Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage18Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage19Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage20Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage21Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage22Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage23Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage24Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage25Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage26Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage2Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage4Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage5Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage6Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage8Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_FirstMortgage9Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_SecuredDebt1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_SecuredDebt2Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_SecuredDebt3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_SecuredDebt4Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_SecuredDebt5Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_SecuredDebt6Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_SecuredDebt7Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_StateRevolvingTrustBond1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_StateRevolvingTrustBondMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_StateRevolvingTrustNote1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_StateRevolvingTrustNote2Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_StateRevolvingTrustNote3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_StateRevolvingTrustNote4Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_StateRevolvingTrustNote5Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_StateRevolvingTrustNote6Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_StateRevolvingTrustNote7Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_StateRevolvingTrustNote8Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_StateRevolvingTrustNote9Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=msex_StateRevolvingTrustNoteMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=us-gaap_SecuredDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=msex_ConvertiblePreferredStock1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=msex_NonredeemablePreferredStock1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_ConvertiblePreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_NonredeemablePreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |