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v3.20.4

Debt - Additional Information (Details) |  | 12 Months Ended |
--- | --- | --- | ---
Sep. 13, 2019 USD ($) | Dec. 31, 2020 USD ($) equipment_note | Dec. 31, 2019 USD ($)
Credit Agreement | Secured Debt |  |  |
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 |  |
Interest rate on borrowings outstanding |  | 2.35% |
Leverage coverage ratio | 3.0 |  |
Interest coverage ratio | 3.0 |  |
Deferred debt issuance costs |  | $ 1,100,000 |
Credit Agreement | Secured Debt | Minimum |  |  |
Debt Instrument [Line Items] |  |  |
Commitment fee on unused capacity | 0.15% |  |
Credit Agreement | Secured Debt | Minimum | Base Rate |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate margin | 0.00% |  |
Credit Agreement | Secured Debt | Minimum | London Interbank Offered Rate (LIBOR) |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate margin | 1.00% |  |
Credit Agreement | Secured Debt | Maximum |  |  |
Debt Instrument [Line Items] |  |  |
Commitment fee on unused capacity | 0.25% |  |
Credit Agreement | Secured Debt | Maximum | Base Rate |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate margin | 0.75% |  |
Credit Agreement | Secured Debt | Maximum | London Interbank Offered Rate (LIBOR) |  |  |
Debt Instrument [Line Items] |  |  |
Interest rate margin | 1.75% |  |
Credit Agreement | Secured Debt | Letter of Credit |  |  |
Debt Instrument [Line Items] |  |  |
Maximum borrowing capacity | $ 150,000,000 |  |
Letters of credit outstanding |  | 10,400,000 | $ 10,600,000
Credit Agreement | Secured Debt | Letter of Credit | Insurance Program Obligations |  |  |
Debt Instrument [Line Items] |  |  |
Letters of credit outstanding |  | 9,800,000 | 10,000,000.0
Credit Agreement | Secured Debt | Letter of Credit | Contract Performance Obligations |  |  |
Debt Instrument [Line Items] |  |  |
Letters of credit outstanding |  | $ 600,000 | $ 600,000
Credit Agreement | Secured Debt | Revolving Loans and Letters of Credit |  |  |
Debt Instrument [Line Items] |  |  |
Maximum borrowing capacity | $ 75,000,000 |  |
Credit Agreement | Secured Debt | Non-performance Letters Of Credit | Minimum |  |  |
Debt Instrument [Line Items] |  |  |
Letter of credit facility commitment percentage | 1.00% |  |
Credit Agreement | Secured Debt | Non-performance Letters Of Credit | Maximum |  |  |
Debt Instrument [Line Items] |  |  |
Letter of credit facility commitment percentage | 1.75% |  |
Credit Agreement | Secured Debt | Performance letters of credit | Minimum |  |  |
Debt Instrument [Line Items] |  |  |
Letter of credit facility commitment percentage | 0.50% |  |
Credit Agreement | Secured Debt | Performance letters of credit | Maximum |  |  |
Debt Instrument [Line Items] |  |  |
Letter of credit facility commitment percentage | 0.875% |  |
Master Loan Agreement | Notes Payable to Banks |  |  |
Debt Instrument [Line Items] |  |  |
Number of equipment notes | equipment_note |  | 4 |

X
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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 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 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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