Debt - Summary of Scheduled Debt Maturities, Including Balloon Payments (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
2019	$ 0
2020	0
2021	100,000
2022	70,000
2023	125,000
Thereafter	150,000
Total	445,000	$ 380,000
Revolving Facility [Member]
Debt Instrument [Line Items]
2019	0
2020	0
2021	0
2022	70,000
2023	0
Thereafter	0
Total	70,000
Term Loan [Member]
Debt Instrument [Line Items]
2019	0
2020	0
2021	0
2022	0
2023	50,000
Thereafter	0
Total	50,000
Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
2019	0
2020	0
2021	100,000
2022	0
2023	75,000
Thereafter	150,000
Total	$ 325,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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