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Fair Value of Financial Instruments - Carrying Value and Fair Value of Long-Term Debt (Detail) - USD ($) $ in Thousands | Jun. 30, 2020 | Dec. 31, 2019
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Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Carrying Value | $ 349,662 | $ 362,255
Fair Value | 350,169 | 362,663
Revolving Credit Facility Due Mar. 2020 And Nov. 2016 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Carrying Value | 83,985 | 84,255
Fair Value | 83,985 | 84,255
Term Loan, Due Feb. 2024 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Carrying Value | 234,038 | 240,969
Fair Value | 234,038 | 240,969
2.40% Term Loan, Due Jun. 2022 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Carrying Value | 3,200 | 4,012
Fair Value | 3,258 | 4,076
2.05% Term Loan, Due Mar. 2023 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Carrying Value | 16,437 | 19,487
Fair Value | 16,733 | 19,764
1.30% Term Loan, Due Jun. 2023 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Carrying Value | 4,799 | 5,617
Fair Value | 4,834 | 5,624
1.55% Term Loan, Due Sep. 2025 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Carrying Value | 7,203 | 7,915
Fair Value | $ 7,321 | $ 7,975

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- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870 Reference 2: 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(a)(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 3: 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 4: 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 + Details
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