Represents the amount of stock repurchases to maintain maximum net leverage ratio.

No definition available.

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Balance Type:	credit
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- Definition

Represents the number of quarters of capital expenditures, tax provision, dividends and stock repurchase payments used for the calculation of the fixed charge coverage ratio.

+ References

No definition available.

+ Details

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- Definition

Represents the ratio of consolidated adjusted earnings before, interest, taxes, depreciation and amortization, less non-financed capital expenditures, tax provision, dividends and amounts used to repurchase stock to the sum of interest expense and scheduled principal payments of indebtedness required to be maintained under the financial covenants.

+ References

No definition available.

+ Details

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Namespace Prefix:	fix_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the ratio of consolidated total debt to consolidated adjusted earnings before, interest, taxes, depreciation and amortization required to be maintained under the financial covenants.

+ References

No definition available.

+ Details

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- Definition

Represents the net leverage ratio determine after giving effect to stock repurchases for calculation of the fixed charge coverage ratio under the financial covenants.

+ References

No definition available.

+ Details

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- Definition

Represents the net leverage ratio used to determine exclusion of stock repurchases and the payment of dividends for calculation of the fixed charge coverage ratio under the financial covenants.

+ References

No definition available.

+ Details

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- Definition

Represents the aggregate purchase price of current acquisition and acquisitions in the preceding twelve month period used for determining the permitted amount of acquisition per transaction under the financial covenants.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Represents the net leverage ratio as defined in the financial covenants which is used as a basis to determine other restrictions.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of acquisition per transaction permitted under the financial covenants.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the net leverage ratio used to determine the credit availability under the revolving credit facility.

+ References

No definition available.

+ Details

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- Details

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- Definition

Represents the number of interest rate options.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Details

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- Definition

Represents the fees for the letter of credit facility, expressed as a percent based on the ratio of consolidated total indebtedness to credit facility adjusted EBITDA, as defined in the credit agreement.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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- Definition

Represents the number of trailing months used to calculate available credit.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

+ 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 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19

-Article 5

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 210.5-02.20)

-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 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45023-112735

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: 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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

Reference 3: 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

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Balance Type:	credit
Period Type:	instant

- 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

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Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- 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

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Data Type:	num:percentItemType
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Long-Term Debt Obligations (Details 2) (USD $)	3 Months Ended
Long-Term Debt Obligations (Details 2) (USD $)	Mar. 31, 2015 item	Dec. 31, 2014	May 01, 2014
Other disclosures
Current portion of capital lease obligations	$ 299,000us-gaap_CapitalLeaseObligationsCurrent	$ 317,000us-gaap_CapitalLeaseObligationsCurrent
Revolving credit facility
Long-Term Debt Obligations
Borrowing capacity	250,000,000
Outstanding borrowings	36,000,000
Letters of credit amount outstanding	48,000,000
Credit available	164,500,000
Principal financial covenants
Leverage ratio	0.51
Number of quarters of capital expenditures, tax provision, dividends and stock repurchase payments used for calculation of fixed charge coverage ratio	4
Number of interest rate options	2
Debt instrument covenant credit availability ratio	2.75
Number of trailing months used to calculate available credit	12 months
Other disclosures
Weighted average interest rate (as a percent)	1.40%
Revolving credit facility \| EAS
Long-Term Debt Obligations
Borrowing capacity	2,500,000
Credit available	2,500,000
Other disclosures
Weighted average interest rate (as a percent)	2.70%
Revolving credit facility \| Actual
Principal financial covenants
Fixed charge coverage ratio	20.47
Revolving credit facility \| Minimum
Long-Term Debt Obligations
Borrowing capacity	250,000,000
Additional per annum interest margin added under:
Letter of credit fees (as a percent)	1.25%
Commitment fees payable on unused portion of the facility (as a percent)	0.20%
Revolving credit facility \| Minimum \| Covenant Requirement
Principal financial covenants
Net leverage ratio used as basis for other restrictions	2.00
Revolving credit facility \| Minimum \| Actual
Principal financial covenants
Fixed charge coverage ratio	2.00
Revolving credit facility \| Maximum
Long-Term Debt Obligations
Credit available	248,500,000
Principal financial covenants
Permitted amount of acquisitions per transaction	25,000,000
Aggregate purchase price of current acquisition and acquisitions in the preceding 12 month period for determining permitted amount of acquisition per transaction	60,000,000
Additional per annum interest margin added under:
Letter of credit fees (as a percent)	2.00%
Commitment fees payable on unused portion of the facility (as a percent)	0.35%
Revolving credit facility \| Maximum \| Through maturity
Principal financial covenants
Leverage ratio	2.75
Revolving credit facility \| Maximum \| Covenant Requirement
Principal financial covenants
Net leverage ratio used to determine exclusion of stock repurchases and the payment of dividends for calculation of the fixed charge coverage ratio	1.50
Revolving credit facility \| Maximum \| Actual
Principal financial covenants
Amount of stock repurchases to maintain maximum net leverage ratio	25,000,000
Net leverage ratio after giving effect to stock repurchases for calculation of the fixed charge coverage ratio	1.50
Revolving credit facility \| Base rate \| Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA: Less than 0.75
Market rates relating to interest options
Interest rate margin (as a percent)	0.25%
Additional per annum interest margin added under:
Additional per annum interest margin (as a percent)	0.25%
Revolving credit facility \| Base rate \| Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA: 0.75 to 1.50
Market rates relating to interest options
Interest rate margin (as a percent)	0.50%
Additional per annum interest margin added under:
Additional per annum interest margin (as a percent)	0.50%
Revolving credit facility \| Base rate \| Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA: 1.50 to 2.25
Market rates relating to interest options
Interest rate margin (as a percent)	0.75%
Additional per annum interest margin added under:
Additional per annum interest margin (as a percent)	0.75%
Revolving credit facility \| Base rate \| Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA: 2.25 or greater
Market rates relating to interest options
Interest rate margin (as a percent)	1.00%
Additional per annum interest margin added under:
Additional per annum interest margin (as a percent)	1.00%
Revolving credit facility \| Eurodollar rate \| Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA: Less than 0.75
Market rates relating to interest options
Interest rate margin (as a percent)	1.25%
Additional per annum interest margin added under:
Additional per annum interest margin (as a percent)	1.25%
Revolving credit facility \| Eurodollar rate \| Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA: 0.75 to 1.50
Market rates relating to interest options
Interest rate margin (as a percent)	1.50%
Additional per annum interest margin added under:
Additional per annum interest margin (as a percent)	1.50%
Revolving credit facility \| Eurodollar rate \| Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA: 1.50 to 2.25
Market rates relating to interest options
Interest rate margin (as a percent)	1.75%
Additional per annum interest margin added under:
Additional per annum interest margin (as a percent)	1.75%
Revolving credit facility \| Eurodollar rate \| Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA: 2.25 or greater
Market rates relating to interest options
Interest rate margin (as a percent)	2.00%
Additional per annum interest margin added under:
Additional per annum interest margin (as a percent)	2.00%
Notes to former owners
Long-Term Debt Obligations
Outstanding borrowings	1,000,000
Other disclosures
Weighted average interest rate (as a percent)	2.50%
Other debt \| Dyna Ten
Other disclosures
Capital lease obligation pertaining to acquisition in northern Texas	800,000		700,000
Current portion of capital lease obligations	$ 300,000