Schedule Of Income Taxes [Line Items]

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 8
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32621-109319

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

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- Definition

Amount of income tax expense for remeasurement of deferred tax asset from change in tax rate pursuant to Tax Cuts and Jobs Act.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319

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- Definition

Amount of income tax expense (benefit) for measurement period adjustment from accounting for tax effect pursuant to Tax Cuts and Jobs Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2A
-Subparagraph (SAB Topic 5.EE.Q2(f))
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Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2018	Dec. 31, 2017	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Income Taxes [Line Items]
Income tax expense due to re-measurement of deferred tax assets and liabilities as result of changes in federal tax rate		$ 13,400
Income tax benefit	$ 3,000
Valuation allowance related to gross deferred tax assets			$ 5,489	$ 5,134
Deferred tax assets, net operating loss carry forwards			54,900
PENNSYLVANIA
Schedule Of Income Taxes [Line Items]
Valuation allowance related to gross deferred tax assets			$ 5,500	$ 5,100