XML 37 R47.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Debt and Borrowing Arrangements (Details Textual) (USD $) In Millions, unless otherwise specified | 12 Months Ended | 1 Months Ended |
--- | --- | --- | ---
Dec. 31, 2014 | Dec. 21, 2011 | Dec. 31, 2013
Debt Instrument [Line Items] |  |  |
Letters of Credit Outstanding, Amount | 19.3 us-gaap_LettersOfCreditOutstandingAmount |  | $ 18.4 us-gaap_LettersOfCreditOutstandingAmount
Borrowings Available Under The Credit Agreement | 155.7 us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity |  |
Maximum [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Variable rate basis | LIBOR |  |
Maximum [Member] | London Interbank Offered Rate [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate margin (as a percent) | 2.00%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_RangeAxis = us-gaap_MaximumMember / us-gaap_VariableRateAxis = myrg_LondonInterbankOfferedRateMember |  |
Revolving Credit Facility [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Facing fees (as a percent) | 0.125%myrg_LetterOfCreditFrontingFees / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember |  |
Commitment fee on unused portion of facility (as a percent) | 0.20%us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember |  |
Revolving Credit Facility [Member] | ABR [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Variable rate basis | ABR |  |
Revolving Credit Facility [Member] | Prime Rate [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Variable rate basis | Prime Rate |  |
Revolving Credit Facility [Member] | Federal Funds Effective Rate [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate margin (as a percent) | 0.50%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_VariableRateAxis = myrg_DebtInstrumentVariableRateBaseFederalFundsEffectiveRateMember |  |
Variable rate basis | Federal Funds Effective Rate |  |
Revolving Credit Facility [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate margin (as a percent) | 1.00%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember |  |
Variable rate basis | LIBOR |  |
Revolving Credit Facility [Member] | Maximum [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate margin (as a percent) | 1.00%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MaximumMember |  |
Revolving Credit Facility [Member] | Minimum [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate margin (as a percent) | 0.00%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MinimumMember |  |
Revolving Credit Facility [Member] | Minimum [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate margin (as a percent) | 1.00%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_DebtInstrumentAxis = us-gaap_RevolvingCreditFacilityMember / us-gaap_RangeAxis = us-gaap_MinimumMember / us-gaap_VariableRateAxis = us-gaap_LondonInterbankOfferedRateLIBORMember |  |
Swing line Loans [Member] | Maximum [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Maximum borrowing capacity |  | 25.0 us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity / us-gaap_DebtInstrumentAxis = myrg_SwingLineLoansMember / us-gaap_RangeAxis = us-gaap_MaximumMember |
Letter of Credit [Member] | Maximum [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Letter of credit fee (as a percent) | 2.00%myrg_LetterOfCreditFeesPercentage / us-gaap_DebtInstrumentAxis = us-gaap_LetterOfCreditMember / us-gaap_RangeAxis = us-gaap_MaximumMember |  |
Letter of Credit [Member] | Minimum [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Letter of credit fee (as a percent) | 1.00%myrg_LetterOfCreditFeesPercentage / us-gaap_DebtInstrumentAxis = us-gaap_LetterOfCreditMember / us-gaap_RangeAxis = us-gaap_MinimumMember |  |
Standby Letters of Credit [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Letters of Credit Outstanding, Amount | 19.3 us-gaap_LettersOfCreditOutstandingAmount / us-gaap_DebtInstrumentAxis = us-gaap_StandbyLettersOfCreditMember |  |
Interest rate (as a percent) | 1.125%us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd / us-gaap_DebtInstrumentAxis = us-gaap_StandbyLettersOfCreditMember |  |
Syndicated Credit Agreement [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Option to increase borrowing capacity |  | 75.0 myrg_LineOfCreditFacilityOptionToIncreaseMaximumBorrowingCapacity / us-gaap_LongtermDebtTypeAxis = myrg_SyndicatedCreditAgreementMember |
Maximum borrowing capacity |  | $ 175.0 us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity / us-gaap_LongtermDebtTypeAxis = myrg_SyndicatedCreditAgreementMember |
Term of the credit agreement |  | 5 years |
Syndicated Credit Agreement [Member] | Maximum [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Leveraged debt ratio | 3.0 myrg_DebtInstrumentCovenantLeveragedDebtRatio / us-gaap_LongtermDebtTypeAxis = myrg_SyndicatedCreditAgreementMember / us-gaap_RangeAxis = us-gaap_MaximumMember |  |
Syndicated Credit Agreement [Member] | Minimum [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest coverage ratio | 3.0 myrg_DebTinstrumentCovenantInterestCoverageRatio / us-gaap_LongtermDebtTypeAxis = myrg_SyndicatedCreditAgreementMember / us-gaap_RangeAxis = us-gaap_MinimumMember |  |

X
- Definition Represent the minimum interest coverage ratio under the credit agreement. + References No definition available. + Details
Name: | myrg_DebTinstrumentCovenantInterestCoverageRatio
Namespace Prefix: | myrg_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the maximum leveraged debt ratio under the credit agreement. + References No definition available. + Details
Name: | myrg_DebtInstrumentCovenantLeveragedDebtRatio
Namespace Prefix: | myrg_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the fees for the letter of credit facility, expressed as a percentage. + References No definition available. + Details
Name: | myrg_LetterOfCreditFeesPercentage
Namespace Prefix: | myrg_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The percentage of fronting fees paid on the outstanding amount of letters of credit. + References No definition available. + Details
Name: | myrg_LetterOfCreditFrontingFees
Namespace Prefix: | myrg_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the option to increase maximum borrowings on the credit facility. + References No definition available. + Details
Name: | myrg_LineOfCreditFacilityOptionToIncreaseMaximumBorrowingCapacity
Namespace Prefix: | myrg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentDescriptionOfVariableRateBasis
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_DebtInstrumentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentTerm
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. + References No definition available. + Details
Name: | us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The effective interest rate at the end of the reporting period. + 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(b),22(b)) -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 19, 22 -Article 5 + Details
Name: | us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + 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(b),22(b)) -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 19, 22 -Article 5 + Details
Name: | us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding). + 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(b),22(b)) -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 19, 22 -Article 5 + Details
Name: | us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility. + References No definition available. + Details
Name: | us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

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

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

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

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

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=myrg_SyndicatedCreditAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |