Financial Instruments - Narrative (Details) - USD ($)	3 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Share price (in dollars per share)	$ 66.59
Accrued interest	$ 44,000	$ 108,000
Available-for-sale, credit loss	$ 0	$ 0
Interest Rate Lock Commitments \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loan commitments, term	30 days
Interest Rate Lock Commitments \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loan commitments, term	90 days
1.75% Convertible Senior Notes due 2023
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Aggregated principal amount	$ 23,777,000
0% Convertible Senior Notes due 2025
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Aggregated principal amount	661,250,000
0.5% Convertible Senior Notes Due 2027
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Aggregated principal amount	$ 500,000,000

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- Definition

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

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- Definition

Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

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