Fair Value Measurements and Derivative Instruments (Unrealized Holding Losses) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Less than 12 continuous months	$ 35,784	$ 48,318
Greater than 12 continuous months	28,235	177,331
Total	64,019	225,649
Gross unrealized losses
Less than 12 continuous months	360	847
Greater than 12 continuous months	364	4,355
Total	$ 724	$ 5,202

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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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