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- Definition

Debt Instrument, Floor Rate of Basis Spread On Variable Rate

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- Definition

Debt Instrument, Optional Extension Term

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- Definition

Debt Instrument, Termination Notice Period

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Amount of amortization expense attributable to debt issuance costs.

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Amount of net assets (liabilities).

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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Weighted average interest rate of debt outstanding.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Debt - Narrative (Details) - USD ($)	12 Months Ended
Debt - Narrative (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Jul. 23, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Inventory	$ 74,590,000	$ 22,694,000
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	247,448,000	439,055,000		$ 212,658,000	$ 67,845,000
1.75% Convertible Senior Notes due 2023
Debt Instrument [Line Items]
Stated interest rate			1.75%
Amortization of debt issuance costs	(724,000)	(304,000)
Interest expense, debt	2,516,000	1,097,000
Debt instrument, face amount			$ 143,750,000
Debt instrument, interest rate, effective percentage			7.25%
Fair Value, Inputs, Level 2 \| 1.75% Convertible Senior Notes due 2023
Debt Instrument [Line Items]
Debt instrument, fair value	142,672,000	$ 117,875,000
Revolving Credit Facility
Debt Instrument [Line Items]
Net Assets	16,200,000
Inventory	7,456,000
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 5,663,000
Debt, weighted average interest rate	4.45%
Amortization of debt issuance costs	$ (256,000)
Interest expense, debt	$ 17,000
Goldman Sachs Bank USA \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, term	6 months
Western Alliance Bank \| Warehouse Agreement Borrowings \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.00%
Stated interest rate	3.50%
Debt, weighted average interest rate	3.79%	5.26%
Texas Capital Bank, N.A. \| Warehouse Agreement Borrowings
Debt Instrument [Line Items]
Debt instrument, decrease in rate of interest accruing on outstanding principal	0.50%
Stated interest rate	3.50%
Debt, weighted average interest rate	3.51%	4.11%
Minimum \| Goldman Sachs Bank USA \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, floor rate of basis spread on variable rate	0.50%
Maximum \| Goldman Sachs Bank USA \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.65%
Line of Credit \| Revolving Credit Facility \| Flagstar Warehouse Credit Facility [Member]
Debt Instrument [Line Items]
Stated interest rate	3.00%
Debt, weighted average interest rate	3.69%
Debt instrument, termination notice period	30 days
Line of Credit \| Revolving Credit Facility \| London Interbank Offered Rate (LIBOR) \| Flagstar Warehouse Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.00%