Significant accounting policies.

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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- Definition

Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income tax settlements. Including, but not limited to, domestic tax settlement, foreign tax settlement, state and local tax settlement, and other tax settlements.

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of lessee's right to use underlying asset under operating lease.

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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Oct. 31, 2019	Jan. 01, 2019
Significant Accounting Policies [Line Items]
Impairment losses on long-lived assets	$ 0	$ 0	$ 0
Common stock, shares outstanding (in shares)	51,617,639	37,676,760
Operating lease assets	$ 21,158,000	$ 0
Total operating lease liabilities	17,651,000				$ 11,900,000
Build to suit asset	$ 8,163,000	14,670,000
Minimum
Significant Accounting Policies [Line Items]
Income tax examination, likelihood percentage	50.00%
Construction in progress
Significant Accounting Policies [Line Items]
Build to suit asset	$ 169,000	11,914,000			11,900,000
Accounting Standards Update 2016-02
Significant Accounting Policies [Line Items]
Operating lease assets				$ 21,200,000	800,000
Total operating lease liabilities				$ 17,000,000.0	$ 800,000
CRL Construction Loan
Significant Accounting Policies [Line Items]
Fair value of outstanding notes payable to related party		$ 1,100,000