Income Taxes, Accounting for Uncertainty in Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Accounting for Uncertainty in Income Taxes [Abstract]
Unrecognized tax benefits	$ 0	$ 0
Change in unrecognized tax benefits	0	$ 5
Unrecognized interest and penalties	$ 0
Internal Revenue Service (IRS) [Member]
Accounting for Uncertainty in Income Taxes [Abstract]
Tax year subject to examination	2017 2016 2015
California Franchise Tax Board [Member]
Accounting for Uncertainty in Income Taxes [Abstract]
Tax year subject to examination	2017 2016 2015 2014

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Amount of increase (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in tax returns.

+ References

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