Goodwill and Intangibles Assets - Changes in Carrying Amount of Goodwill (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Goodwill [Roll Forward]
Beginning Balance	$ 6,129,000	$ 10,488,000
Impairment	0	(4,359,000)
Ending Balance	6,129,000	6,129,000
Construction
Goodwill [Roll Forward]
Beginning Balance	0	4,359,000
Impairment	0	(4,359,000)
Ending Balance	0	0
Service
Goodwill [Roll Forward]
Beginning Balance	6,129,000	6,129,000
Impairment	0	0
Ending Balance	$ 6,129,000	$ 6,129,000

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13854-109267

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13777-109266

Name:	us-gaap_GoodwillImpairmentLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration