Debt Instrument, Additional Basis Spread On Variable Rate

No definition available.

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Namespace Prefix:	fi_
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Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Covenant, Consolidated EBITDA, Minimum

+ References

No definition available.

+ Details

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

- Definition

Federal Funds Effective Rate, Interest Rate Floor

+ References

No definition available.

+ Details

Name:	fi_FederalFundsEffectiveRateInterestRateFloor
Namespace Prefix:	fi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Covenant Term, Minimum Fixed Charges

+ References

No definition available.

+ Details

Name:	fi_LineofCreditFacilityCovenantTermMinimumFixedCharges
Namespace Prefix:	fi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line of Credit Facility, Covenant Term, Minimum Fixed Charges, Percentage

+ References

No definition available.

+ Details

Name:	fi_LineofCreditFacilityCovenantTermMinimumFixedChargesPercentage
Namespace Prefix:	fi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Maximum Borrowing Capacity, Potential Increase

+ References

No definition available.

+ Details

Name:	fi_LineofCreditFacilityMaximumBorrowingCapacityPotentialIncrease
Namespace Prefix:	fi_
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

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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

- 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://fasb.org/us-gaap/role/ref/legacyRef
-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://fasb.org/us-gaap/role/ref/legacyRef
-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 3: http://fasb.org/us-gaap/role/ref/legacyRef
-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_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Period remaining on line of credit facility before it terminates, 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_LineOfCreditFacilityExpirationPeriod
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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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

Name:	us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=fi_NewABLCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=fi_RevolvingCreditFacilityMaturingAugust2018Member
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Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SecuredDebtMember
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Balance Type:
Period Type:

- Details

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- Details

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- Details

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- Details

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- Details

Name:	us-gaap_VariableRateAxis=us-gaap_EurodollarMember
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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LetterOfCreditMember
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Balance Type:
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- Details

Name:	us-gaap_CreditFacilityAxis=fi_RevolvingCreditFacilitySwingLineLoanMember
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Debt - Credit Facilities (Details)	Nov. 05, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Revolving Credit Facility \| New ABL Credit Facility
Line of Credit Facility [Line Items]
Covenant, consolidated EBITDA, minimum	1.0
Covenant, minimum fixed charges amount	$ 12,500,000.0
Covenant, minimum fixed charges percentage	15.00%
Revolving Credit Facility \| Lines of credit \| Revolving Credit Facility Maturing August 2018
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 100,000,000.0
Letters of credit, amount outstanding			$ 2,800,000
Revolving Credit Facility \| Lines of credit \| New ABL Credit Facility
Line of Credit Facility [Line Items]
Letters of credit, amount outstanding		4,900,000
Revolving Credit Facility \| Secured Debt \| New ABL Credit Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 100,000,000.0
Expiration period	5 years
Maximum additional borrowing capacity	$ 200,000,000
Federal funds effective rate	0.00%
Basis spread on variable rate	0.50%
Outstanding indebtedness		0
Available borrowing capacity		69,700,000
Revolving Credit Facility \| Secured Debt \| New ABL Credit Facility \| Minimum
Line of Credit Facility [Line Items]
Unused capacity, commitment fee	0.25%
Revolving Credit Facility \| Secured Debt \| New ABL Credit Facility \| Maximum
Line of Credit Facility [Line Items]
Unused capacity, commitment fee	0.375%
Revolving Credit Facility \| Secured Debt \| New ABL Credit Facility \| London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.00%
Revolving Credit Facility \| Secured Debt \| New ABL Credit Facility \| Alternate Base Rate \| Minimum
Line of Credit Facility [Line Items]
Additional spread on variable rate	1.00%
Revolving Credit Facility \| Secured Debt \| New ABL Credit Facility \| Alternate Base Rate \| Maximum
Line of Credit Facility [Line Items]
Additional spread on variable rate	1.50%
Revolving Credit Facility \| Secured Debt \| New ABL Credit Facility \| Eurodollar \| Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.00%
Revolving Credit Facility \| Secured Debt \| New ABL Credit Facility \| Eurodollar \| Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.50%
Letter of Credit \| Lines of credit \| Revolving Credit Facility Maturing August 2018
Line of Credit Facility [Line Items]
Maximum borrowing capacity		20,000,000.0
Letter of Credit \| Secured Debt \| New ABL Credit Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 15,000,000.0
Swingline loans \| Lines of credit \| Revolving Credit Facility Maturing August 2018
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 10,000,000.0