Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 30, 2019	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, percentage of outstanding stock maximum	5.00%
Share-based compensation arrangement by share-based payment award, percentage of outstanding and available for grant, maximum	10.00%
Compensation expense, share-based payment plans	$ 753	$ 1,024
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Volatility rate	9.90%	10.10%
Risk-free interest rate	2.50%	2.50%
Expected dividend yield	0.70%	0.70%
Expected life of awards (years)	7 years 4 months 24 days	9 years
Stock option plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense, share-based payment plans	$ 149	$ 182
Stock options awarded, term (years)	10 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding, beginning balance	1,466,264
Granted	27,800
Exercised	0
Forfeited	(3,200)
Outstanding, ending balance	1,490,864
Exercisable, ending balance	887,114
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Outstanding, weighted average exercise price, beginning balance	$ 13.94
Granted, weighted average exercise price	21.1
Exercised, weighted average exercise price	0.00
Forfeited, weighted average exercise price	16.37
Outstanding, weighted average exercise price, ending balance	14.07
Exercisable, weighted average exercise price, ending balance	$ 12.22
Outstanding, weighted average remaining contractual life (years)	5 years 8 months 9 days
Exercisable, weighted average remaining contractual life (years)	4 years 4 months 24 days
Outstanding, aggregate intrinsic value	$ 10,481
Exercisable, aggregate intrinsic value	7,882
Outstanding, unrecognized compensation cost	$ 1,353
Employee service share-based compensation, nonvested awards, total compensation cost not yet recognized, period for recognition	2 years 1 month 10 days
Stock-settled stock appreciation rights (SSARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense, share-based payment plans	$ 95	160
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested, beginning balance	380,982
Granted	0
Forfeited	0
Vested	(115,080)
Unvested, ending balance	265,902
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Unvested, weighted average award date value, beginning balance	$ 3.42
Granted, weighted average award date value	0.00
Forfeited, weighted average award date value	0
Vested, weighted average award date value	3.31
Unvested, weighted average award date value, ending balance	$ 3.47
Weighted average remaining contractual life (years)	2 years 2 months 5 days
Unrecognized compensation cost	$ 829
Aggregate intrinsic value	5,611
Restricted stock units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense, share-based payment plans	$ 233	425
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested, beginning balance	247,838
Granted	29,046
Forfeited	0
Vested	(45,546)
Unvested, ending balance	231,338
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Unvested, weighted average award date value, beginning balance	$ 15.68
Granted, weighted average award date value	20.36
Forfeited, weighted average award date value	0
Vested, weighted average award date value	12.64
Unvested, weighted average award date value, ending balance	$ 16.86
Weighted average remaining contractual life (years)	2 years 3 months 4 days
Unrecognized compensation cost	$ 2,086
Aggregate intrinsic value	$ 4,881
Employee PRSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Granted	29,046
Unvested, ending balance	196,930
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Unvested, weighted average award date value, ending balance	$ 16.79
Weighted average remaining contractual life (years)	2 years 9 months 18 days
Unrecognized compensation cost	$ 1,831
Aggregate intrinsic value	$ 4,155
Nonemployee Director RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested, ending balance	34,408
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Unvested, weighted average award date value, ending balance	$ 17.27
Weighted average remaining contractual life (years)	1 year
Unrecognized compensation cost	$ 255
Aggregate intrinsic value	726
The Davey Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense, share-based payment plans	$ 276	$ 257
Employee stock purchase plan, service period	1 year
Employee stock purchase plan, percentage of market price, purchase date	85.00%
Employee stock purchase plan, discount from market price, purchase date	15.00%

Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Market Price, Purchase Date

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Share-based compensation arrangement by share-based payment award, percentage of outstanding and available for grant, maximum

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No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested options awarded to employees as compensation.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Discount rate from fair value on purchase date that participants pay for shares.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Weighted average expected volatility rate of share-based compensation awards.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Net number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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No definition available.

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Intrinsic value of equity-based compensation awards not vested. Excludes stock and unit options.

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No definition available.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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