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Long-Term Debt (Details) - USD ($) | 3 Months Ended |  |  |
--- | --- | --- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020 | Nov. 01, 2016 | Nov. 11, 2013
Debt Instrument [Line Items] |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity, Current | $ 100,000,000.0 |  | $ 175,000,000.0 | $ 250,000,000.0
Allowable Amount For Issuance of Letters of Credit | $ 30,000,000.0 |  |  | $ 20,000,000.0
Debt Instrument, Covenant, Leverage Ratio | 2 |  |  |
Debt Covenant, Minimum Net Income Requirement | $ 1.00 |  |  |
Debt Covenant, Minimum Tangible Net Worth | 250,000,000.0 |  |  |
Long-term Debt | 0 | $ 0 |  |
Letters of Credit Outstanding, Amount | 11,500,000 |  |  |
Line of Credit Facility, Current Borrowing Capacity | $ 88,500,000 |  |  |
Prime Rate [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 0.00% |  |  |
Minimum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage | 0.0725% |  |  |
Minimum [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 0.70% |  |  |
Maximum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage | 0.175% |  |  |
Maximum [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 0.90% |  |  |
Accordion Feature [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity, Current | $ 100,000,000.0 |  |  |

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- Definition Allowable amount for issuance of letters of credit under the credit facility. + References No definition available. + Details
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X
- Definition Debt Covenant, Minimum Net Income Requirement + References No definition available. + Details
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- Definition Debt Covenant, Minimum Tangible Net Worth + References No definition available. + Details
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- Definition Debt Instrument, Covenant, Leverage Ratio + References No definition available. + Details
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- 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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- 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 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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X
- 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=119400593&loc=d3e572229-122910 + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any 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=6877327&loc=d3e13212-122682 + 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=6877327&loc=d3e13212-122682 + Details
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- 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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