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v3.21.1

Debt - Additional information (Details) |  | 3 Months Ended |
--- | --- | --- | ---
Sep. 13, 2019 USD ($) | Mar. 31, 2021 USD ($) equipment_note | Dec. 31, 2020 USD ($)
Revolving Loans |  |  |
Debt Instrument [Line Items] |  |  |
Debt instrument term |  | 5 years |
Secured Debt | Credit Agreement |  |  |
Debt Instrument [Line Items] |  |  |
Debt instrument term | 5 years |  |
Maximum borrowing capacity | $ 375,000,000 |  |
Option to increase borrowing capacity | $ 200,000,000 |  |
Percentage of capital stock from direct foreign subsidiaries | 65.00% |  |
Debt instrument covenant leveraged debt ratio restriction | 2.50 |  |
Debt instrument restricted maximum liquidity | $ 50,000,000 |  |
Leverage coverage ratio | 3.0 |  |
Interest coverage ratio | 3.0 |  |
Deferred debt issuance costs |  | $ 1,100,000 |
Secured Debt | Credit Agreement | Minimum |  |  |
Debt Instrument [Line Items] |  |  |
Commitment fee on unused capacity | 0.15% |  |
Secured Debt | Credit Agreement | Maximum |  |  |
Debt Instrument [Line Items] |  |  |
Commitment fee on unused capacity | 0.25% |  |
Secured Debt | Credit Agreement | Base Rate | Minimum |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate margin | 0.00% |  |
Secured Debt | Credit Agreement | Base Rate | Maximum |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate margin | 0.75% |  |
Secured Debt | Credit Agreement | London Interbank Offered Rate (LIBOR) | Minimum |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate margin | 1.00% |  |
Secured Debt | Credit Agreement | London Interbank Offered Rate (LIBOR) | Maximum |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate margin | 1.75% |  |
Secured Debt | Credit Agreement | Letter of Credit |  |  |
Debt Instrument [Line Items] |  |  |
Maximum borrowing capacity | $ 150,000,000 |  |
Letters of credit outstanding |  | 12,300,000 | $ 10,400,000
Secured Debt | Credit Agreement | Letter of Credit | Insurance Program Obligations |  |  |
Debt Instrument [Line Items] |  |  |
Letters of credit outstanding |  | 12,300,000 | 9,800,000
Secured Debt | Credit Agreement | Letter of Credit | Contract Performance Obligations |  |  |
Debt Instrument [Line Items] |  |  |
Letters of credit outstanding |  |  | 600,000
Secured Debt | Credit Agreement | Revolving loans and letters of credit |  |  |
Debt Instrument [Line Items] |  |  |
Maximum borrowing capacity | $ 75,000,000 |  |
Secured Debt | Credit Agreement | Non-performance Letters Of Credit | Minimum |  |  |
Debt Instrument [Line Items] |  |  |
Letter of credit facility commitment percentage | 1.00% |  |
Secured Debt | Credit Agreement | Non-performance Letters Of Credit | Maximum |  |  |
Debt Instrument [Line Items] |  |  |
Letter of credit facility commitment percentage | 1.75% |  |
Secured Debt | Credit Agreement | Performance letters of credit | Minimum |  |  |
Debt Instrument [Line Items] |  |  |
Letter of credit facility commitment percentage | 0.50% |  |
Secured Debt | Credit Agreement | Performance letters of credit | Maximum |  |  |
Debt Instrument [Line Items] |  |  |
Letter of credit facility commitment percentage | 0.875% |  |
Secured Debt | Credit Agreement | Revolving Loans |  |  |
Debt Instrument [Line Items] |  |  |
Debt outstanding under facility |  | $ 0 | $ 0
Notes Payable to Banks | Master Loan Agreement |  |  |
Debt Instrument [Line Items] |  |  |
Number of equipment notes (equipment note) | equipment_note |  | 4 |

X
- Definition Represent the minimum interest coverage ratio under the credit agreement. + References No definition available. + Details
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- Definition Threshold of debt coverage ration at which the credit agreement restricts certain types of payments. + References No definition available. + Details
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- Definition Amount of company's consolidated liquidity restricted. + References No definition available. + Details
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- Definition The Company has the option to expand the debt coverage ratio in the event of an acquisition. + References No definition available. + Details
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- Definition Represents the option to increase maximum borrowings on the credit facility. + References No definition available. + Details
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- Definition Percentage of capital stock from direct foreign subsidiaries pledged as collateral for a debt. + References No definition available. + Details
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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 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
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- Definition Amount, after 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 + Details
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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)) -URI http://asc.fasb.org/extlink&oid=120391452&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=120398452&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=120400017&loc=d3e572229-122910 + Details
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- Definition The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used. + References No definition available. + Details
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- 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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