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

No definition available.

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- 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

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- Definition

Amount, before accumulated amortization, of debt issuance costs related to line of credit arrangements. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section S45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68176171&loc=SL68176184-208336

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- 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))
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-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Topic 944
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-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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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

The effective interest rate during the reporting period.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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

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

- Definition

Indebtedness divided by net capital.

+ References

No definition available.

+ Details

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- Definition

The cash outflow for the settlement of obligation drawn from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Debt Instrument, Debt Default, Basis Spread Over Applicable Interest Rate

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Line of Credit Facility, Covenant Terms, Minimum Available Borrowings to Satisfy Covenant

+ References

No definition available.

+ Details

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Namespace Prefix:	wfx_
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Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Covenant Terms, Minimum Liquidity

+ References

No definition available.

+ Details

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Namespace Prefix:	wfx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line of Credit Facility, Debt Issuance Costs, Percentage, Annually

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Option, Additional Maximum Borrowing Capacity

+ References

No definition available.

+ Details

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Namespace Prefix:	wfx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Periodic Payment, Principal, Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	wfx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Repayment of Long-Term Lines of Credit, Interest

+ References

No definition available.

+ Details

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Namespace Prefix:	wfx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Repayment of Long-Term Lines of Credit, Principal

+ References

No definition available.

+ Details

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Namespace Prefix:	wfx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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DEBT - Additional Information (Detail) - USD ($)				3 Months Ended		6 Months Ended		12 Months Ended
DEBT - Additional Information (Detail) - USD ($)	Jan. 01, 2021	Jan. 31, 2019	Mar. 03, 2015	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2020	Jan. 17, 2018
Debt Instrument [Line Items]
Debt issuance cost					$ 4,600,000
Principal payment						$ 12,500,000	$ 7,500,000
Revolving credit facility \| Amended Credit Agreement
Debt Instrument [Line Items]
Repayment of outstanding balance					354,500,000
Issuance fees per annum			0.125%
Revolving credit facility \| Amended Credit Agreement \| Minimum
Debt Instrument [Line Items]
Commitment fee percentage of unused borrowings			0.20%
Revolving credit facility \| Amended Credit Agreement \| Maximum
Debt Instrument [Line Items]
Commitment fee percentage of unused borrowings			0.35%
Revolving credit facility \| Amended Credit Agreement \| Base rate \| Minimum
Debt Instrument [Line Items]
Debt basis spread on variable rate			0.50%
Revolving credit facility \| Amended Credit Agreement \| Base rate \| Maximum
Debt Instrument [Line Items]
Debt basis spread on variable rate			1.25%
Revolving credit facility \| Amended Credit Agreement \| LIBOR
Debt Instrument [Line Items]
Debt basis spread on variable rate			1.00%
Revolving credit facility \| Amended Credit Agreement \| LIBOR \| Minimum
Debt Instrument [Line Items]
Debt basis spread on variable rate			1.50%
Revolving credit facility \| Amended Credit Agreement \| LIBOR \| Maximum
Debt Instrument [Line Items]
Debt basis spread on variable rate			2.25%
Revolving credit facility \| Amended Credit Agreement \| Federal funds rate
Debt Instrument [Line Items]
Debt basis spread on variable rate			0.50%
Revolving credit facility \| Amended Credit Agreement \| Applicable interest rate
Debt Instrument [Line Items]
Debt basis spread over applicable interest rate			2.00%
Revolving credit facility \| Second Amended & Restated Credit Agreement
Debt Instrument [Line Items]
Credit facility				$ 400,000,000		400,000,000			$ 400,000,000
Additional borrowing capacity									300,000,000
Repayment of outstanding balance					$ 68,900,000
Maximum leverage ratio			3.25
Minimum liquidity to satisfy covenant terms			$ 250,000,000.0
Availability of revolving credit facility to satisfy covenant term			$ 50,000,000.0
Outstanding borrowing				0		0
Term loan facility \| Amended Credit Agreement
Debt Instrument [Line Items]
Percentage of principal due quarterly			1.25%
Term loan facility \| Second Amended & Restated Credit Agreement
Debt Instrument [Line Items]
Credit facility									$ 500,000,000
Repayment of outstanding balance				11,300,000		25,800,000
Principal payment				6,200,000		12,500,000
Interest payment				$ 5,100,000		$ 13,300,000
Interest rate percentage on term loan						4.27%
Letters of credit \| Amended Credit Agreement
Debt Instrument [Line Items]
Credit facility			$ 10,000,000.0
Letters of credit \| Amended Credit Agreement \| Minimum
Debt Instrument [Line Items]
Commitment fee percentage of unused borrowings			1.50%
Letters of credit \| Amended Credit Agreement \| Maximum
Debt Instrument [Line Items]
Commitment fee percentage of unused borrowings			2.25%
Sublimit for swingline loan advances \| Amended Credit Agreement
Debt Instrument [Line Items]
Credit facility			$ 25,000,000.0
Sublimit for swingline loan advances \| Amended Credit Agreement \| Base rate \| Minimum
Debt Instrument [Line Items]
Debt basis spread on variable rate			0.50%
Sublimit for swingline loan advances \| Amended Credit Agreement \| Base rate \| Maximum
Debt Instrument [Line Items]
Debt basis spread on variable rate			1.25%
Forecast \| Term loan facility \| Amended Credit Agreement
Debt Instrument [Line Items]
Percentage of principal due quarterly	2.50%							1.875%
Subsequent event \| Term loan facility \| Second Amended & Restated Credit Agreement
Debt Instrument [Line Items]
Interest rate percentage on term loan		4.25%