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Long-Term Debt - Summary of Long-Term Debt (Parenthetical) (Detail) | 6 Months Ended |
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Jun. 30, 2019 | Dec. 31, 2018
Debt Instrument [Line Items] |  |
Long-term debt, maturity date | Feb. 08, 2024 |
5.375% Notes, Due Oct. 2020 [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, maturity date | Oct. 31, 2020 |
Interest rate on debt | 5.375% | 5.375%
2.40% Term Loan, Due Jun. 2022 [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, maturity date | Jun. 30, 2022 |
Interest rate on debt | 2.40% | 2.40%
Term Loan, Due Feb. 2024 [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, maturity date | Feb. 29, 2024 |
2.05% Term Loan, Due Mar. 2023 [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, maturity date | Mar. 31, 2023 |
Interest rate on debt | 2.05% | 2.05%
1.30% Term Loan, Due Jun. 2023 [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, maturity date | Jun. 30, 2023 |
Interest rate on debt | 1.30% | 1.30%
1.55% Term Loan, Due Sep. 2025 [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, maturity date | Sep. 30, 2025 |
Interest rate on debt | 1.55% | 1.55%
Revolving Credit Facility, Due Mar. 2020 [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, maturity date | Mar. 31, 2020 |
Revolving Credit Facility, Due Feb. 2024 [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, maturity date | Feb. 29, 2024 |

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- Definition Contractual interest rate for funds borrowed, under the debt 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(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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