Deferred compensation (Stock-based Compensation Cost) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Share-based Payment Arrangement, Noncash Expense [Abstract]
Stock-based compensation cost	$ 101	$ 1,260	$ 771	$ 2,720
Less: stock-based compensation cost capitalized	(7)	(399)	(281)	(1,025)
Stock-based compensation expense	$ 94	$ 861	$ 490	$ 1,695
Number of vested shares repurchased or settled in cash	92,649	126,231	96,505	206,653
Payments for stock-based compensation	$ 53	$ 708	$ 59	$ 1,171
Estimated fair value per share at end of period (in dollars per share)	$ 0.65		$ 0.65
Aggregate intrinsic value of unvested restricted shares outstanding	$ 1,593		$ 1,593
Deferred compensation current	45		45		$ 52
Unrecognized stock-based compensation cost	$ 1,357		$ 1,357
Weighted-average period for unrecognized compensation cost to be recognized			1 year 3 months 18 days

Allocated share based compensation expense benefit.

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- Definition

Employee service share based compensation allocation of recognized period income (costs) capitalized amount.

+ References

No definition available.

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable within one year (or the operating cycle, if longer). Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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- Definition

Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Per share or unit weighted-average intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Amount of cost expensed and capitalized for award under share-based payment arrangement.

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- Definition

Intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

No definition available.

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

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