Available-for-sale securities (Details 2) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Available-for-sale securities [Abstract]
Cost	$ 10,729	$ 10,547	$ 10,101
Gross unrealized gains	3	4	11
Gross unrealized losses	251	130	73
Fair value	10,481	10,421	10,039
Mortgage backed securities
Available-for-sale securities [Abstract]
Cost	10,550	10,342	9,488
Gross unrealized gains	3	4	11
Gross unrealized losses	251	129	72
Fair value	10,302	10,217	9,427
US Treasury securities
Available-for-sale securities [Abstract]
Cost	179	205	613
Gross unrealized gains	0	0	0
Gross unrealized losses	0	1	1
Fair value	$ 179	$ 204	$ 612

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

No definition available.

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- References

No definition available.

+ Details

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

+ Details

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

No definition available.

+ Details

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

No definition available.

+ Details

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