Summary of Significant Accounting Policies (Impact of New Accounting Principles, Balance Sheets) (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current Assets
Accounts receivable, net	$ 1,437	$ 1,011
Inventory	48,771	38,888
Prepaid expenses and other current assets	6,096	4,586
Current liabilities
Accounts payable and accrued expenses	76,220	60,323
Stockholders' Equity:
Retained earnings	$ 168,788	$ 131,344

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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