Long Term Debt - Summary (Detail) - USD ($) $ in Thousands	Mar. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term debt	$ 233,200	$ 233,000
Less current portion	2,330	2,330
Total long-term debt, less current portion	230,870	230,670
Total long-term debt, net of debt issuance costs	$ 227,322	$ 226,961
Weighted-average interest rate (percent)	6.84%	4.71%
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt	$ 3,200	$ 0
Less debt issuance costs - term loan	1,803	1,907
Secured Debt
Debt Instrument [Line Items]
Long-term debt	230,000	233,000
Less debt issuance costs - term loan	1,745	1,802
Total long-term debt, net of debt issuance costs	$ 229,125	$ 228,868

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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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Weighted average interest rate of long-term debt outstanding calculated at point in time.

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