Unaudited Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Common stock [Member]	Paid-in capital [Member]	Treasury stock [Member]	Retained earnings [Member]	Accumulated other comprehensive income (loss) [Member]
Balances at Dec. 31, 2017	$ 168,765	$ 30,943	$ 3,841	$ (51,532)	$ 186,226	$ (713)
Net income	10,434				10,434
Comprehensive income	1,721					1,721
Cumulative effect adjustment \| ASU 2014-09 [Member]	228				228
Cumulative effect adjustment \| ASU 2016-01 [Member]					3,823	(3,823)
Dividends paid	(1,988)				(1,988)
Stock based compensation	245	12	233
Balances at Mar. 31, 2018	179,405	30,955	4,074	(51,532)	198,723	(2,815)
Balances at Dec. 31, 2017	168,765	30,943	3,841	(51,532)	186,226	(713)
Net income	43,158
Comprehensive income	1,107
Balances at Sep. 29, 2018	204,721	30,955	4,074	(52,364)	225,485	(3,429)
Balances at Mar. 31, 2018	179,405	30,955	4,074	(51,532)	198,723	(2,815)
Net income	17,669				17,669
Comprehensive income	(1,315)					(1,315)
Dividends paid	(2,981)				(2,981)
Balances at Jun. 30, 2018	192,778	30,955	4,074	(51,532)	213,411	(4,130)
Net income	15,055				15,055
Comprehensive income	701					701
Purchases of treasury stock	(832)			(832)
Dividends paid	(2,981)				(2,981)
Balances at Sep. 29, 2018	204,721	30,955	4,074	(52,364)	225,485	(3,429)
Balances at Dec. 31, 2018	209,299	30,967	4,230	(52,462)	231,525	(4,961)
Net income	17,297				17,297
Comprehensive income	86					86
Dividends paid	(6,101)				(6,101)
Stock based compensation	73	5	68
Balances at Mar. 30, 2019	220,654	30,972	4,298	(52,462)	242,721	(4,875)
Balances at Dec. 31, 2018	209,299	30,967	4,230	(52,462)	231,525	(4,961)
Net income	28,849
Comprehensive income	(478)
Balances at Sep. 28, 2019	197,915	30,972	4,298	(77,248)	245,332	(5,439)
Balances at Mar. 30, 2019	220,654	30,972	4,298	(52,462)	242,721	(4,875)
Net income	19,972				19,972
Comprehensive income	(272)					(272)
Dividends paid	(2,981)				(2,981)
Balances at Jun. 29, 2019	237,373	30,972	4,298	(52,462)	259,712	(5,147)
Net income	(8,420)				(8,420)
Comprehensive income	(292)					(292)
Purchases of treasury stock	(24,786)			(24,786)
Dividends paid	(2,980)				(2,980)
Dividends payable	(2,980)				(2,980)
Balances at Sep. 28, 2019	$ 197,915	$ 30,972	$ 4,298	$ (77,248)	$ 245,332	$ (5,439)

Dividends payable, common stock.

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Amount of the cumulative effect on retained earnings net of related income tax effect.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Value, after forfeiture, of shares issued under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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