Fair Value Measurements and Derivative Instruments (Unrealized Holding Losses) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Less than 12 continuous months	$ 312,002	$ 132,267
Greater than 12 continuous months	2,294	2,369
Total	314,296	134,636
Gross unrealized losses
Less than 12 continuous months	11,850	1,072
Greater than 12 continuous months	71	76
Total	$ 11,921	$ 1,148

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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), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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