Equity Incentive Plans (Narrative) (Details) $ / shares in Units, $ in Millions	6 Months Ended
Jun. 30, 2021 USD ($) $ / shares shares	Dec. 31, 2020 $ / shares shares
Vesting percentage	100.00%
Vested (in shares)	2,335,068
Assumed 2006 and 2016 Plan [Member]
Reverse stock split ratio	0.0714
Additional awards	0
Minimum [Member] \| Assumed 2006 and 2016 Plan [Member]
Employee service period for share-based award	2 years
Maximum [Member] \| Assumed 2006 and 2016 Plan [Member]
Employee service period for share-based award	4 years
Stock Option [Member]
Common stock closing price \| $ / shares	$ 3.97
Unrecognized compensation cost related to unvested options \| $	$ 4.4
Stock outstanding	9,748
Unvested Restricted Stock Units [Member]
Stock outstanding	30,000
Restricted Stock Awards [Member]
Cancelled (in shares)	924
Stock outstanding	154,141	322,756
Nonvested, RS units, grant date fair value \| $ / shares	$ 27.49	$ 19.55
Stock Options And Restricted Stock Awards [Member]
Weighted-average remaining period for recognition of compensation costs related to unvested options	1 year 10 months 20 days
Equity Incentive Plan 2016 [Member]
Vesting period of share-based compensation award	4 years
Equity Incentive Plan 2016 [Member] \| Maximum [Member]
Expiration period of share-based payment award	10 years

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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Amount of cost to be recognized for option under share-based payment arrangement.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Price of a single share of a number of saleable stocks of a company.

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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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