Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as noncurrent.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes 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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Contractual interest rate for funds borrowed, under the debt agreement.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Jul. 23, 2018
Fair Value, Measurements, Recurring
Assets
Loans held for sale	$ 30,169	$ 4,913
Derivative asset	737	254
Total assets	327,161	430,943
Liabilities
Total liabilities	431	141
Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Loans held for sale	0	0
Derivative asset	0	0
Total assets	195,996	425,776
Liabilities
Total liabilities	0	0
Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2)
Assets
Loans held for sale	30,169	4,913
Derivative asset	25	0
Total assets	130,453	4,913
Liabilities
Total liabilities	407	141
Fair Value, Measurements, Recurring \| Significant Unobservable Inputs (Level 3)
Assets
Loans held for sale	0	0
Derivative asset	712	254
Total assets	712	254
Liabilities
Total liabilities	24	0
U.S. treasury securities \| Fair Value, Measurements, Recurring
Assets
U.S. treasury securities	35,365
U.S. treasury securities	34,954
U.S. treasury securities \| Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
U.S. treasury securities	0
U.S. treasury securities	0
U.S. treasury securities \| Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2)
Assets
U.S. treasury securities	35,365
U.S. treasury securities	34,954
U.S. treasury securities \| Fair Value, Measurements, Recurring \| Significant Unobservable Inputs (Level 3)
Assets
U.S. treasury securities	0
U.S. treasury securities	0
Forward sales commitments \| Fair Value, Measurements, Recurring
Assets
Derivative asset	25
Liabilities
Derivative liability	407	141
Forward sales commitments \| Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Derivative asset	0
Liabilities
Derivative liability	0	0
Forward sales commitments \| Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2)
Assets
Derivative asset	25
Liabilities
Derivative liability	407	141
Forward sales commitments \| Fair Value, Measurements, Recurring \| Significant Unobservable Inputs (Level 3)
Assets
Derivative asset	0
Liabilities
Derivative liability	0	0
Interest rate lock commitments \| Fair Value, Measurements, Recurring
Assets
Derivative asset	712	254
Liabilities
Derivative liability	24
Interest rate lock commitments \| Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Derivative asset	0	0
Liabilities
Derivative liability	0
Interest rate lock commitments \| Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2)
Assets
Derivative asset	0	0
Liabilities
Derivative liability	0
Interest rate lock commitments \| Fair Value, Measurements, Recurring \| Significant Unobservable Inputs (Level 3)
Assets
Derivative asset	712	254
Liabilities
Derivative liability	24
Money market funds \| Fair Value, Measurements, Recurring
Assets
Cash equivalents	195,996	425,776
Money market funds \| Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Cash equivalents	195,996	425,776
Money market funds \| Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2)
Assets
Cash equivalents	0	0
Money market funds \| Fair Value, Measurements, Recurring \| Significant Unobservable Inputs (Level 3)
Assets
Cash equivalents	0	$ 0
U.S. treasury securities \| Fair Value, Measurements, Recurring
Assets
U.S. treasury securities	29,940
U.S. treasury securities \| Fair Value, Measurements, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
U.S. treasury securities	0
U.S. treasury securities \| Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2)
Assets
U.S. treasury securities	29,940
U.S. treasury securities \| Fair Value, Measurements, Recurring \| Significant Unobservable Inputs (Level 3)
Assets
U.S. treasury securities	$ 0
1.75% Convertible Senior Notes due 2023
Liabilities
Stated interest rate			1.75%