Contract Assets and Contract Liabilities (Details 1) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Costs and estimated earnings amounts on uncompleted contracts included in balance sheets
Costs and estimated earnings in excess of billings on uncompleted contracts	$ 12,424	$ 260,325
Billings in excess of costs and estimated earnings on uncompleted contracts	(1,580,481)	(1,334,887)
Net contract assets (liabilities)	$ (1,568,057)	$ (1,074,562)

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
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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
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant