Number of operated wholly owned subsidiaries.

No definition available.

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- Definition

Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

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.

+ References

No definition available.

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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

+ References

No definition available.

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460

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- Definition

The net amount, measured at acquisition-date fair value, of all the assets acquired and liabilities assumed that arise from contingencies and were recognized by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
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Acquisition of a Business - Additional Information (Details)		12 Months Ended
	Oct. 14, 2016 USD ($) Subsidiary $ / shares shares	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Business Acquisition [Line Items]
Goodwill		$ 51,975,000	$ 51,975,000	$ 25,688,000	$ 25,613,000
Ridgestone
Business Acquisition [Line Items]
Business acquisition date of agreement		Oct. 14, 2016
Number of operated wholly owned subsidiaries \| Subsidiary	2
Total consideration included aggregate cash	$ 36,753,000
Issuance of common shares \| shares	4,199,791
Common stock issued price per share \| $ / shares	$ 16.25
Goodwill	$ 26,287,000
Acquisition advisory expenses	1,600,000
Contingent assets or liabilities arising from the acquisition	$ 0