Nature of Business and Significant Accounting Policies - Income taxes (Details) - ASU 2018-02 $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Retained Earnings
Impact of new accounting pronouncement
Cumulative Effect on Retained Earnings, Net of Tax	$ (53)
Accumulated Comprehensive Income
Impact of new accounting pronouncement
Cumulative Effect on Retained Earnings, Net of Tax	$ 53

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22663-107794

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