Derivative and Hedging Instruments - Narrative (Details) - USD ($)	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Derivative loss reclassification from AOCI to income	$ 400,000
Customer Concentration Risk \| Accounts Receivable \| One Customer
Derivative Instruments, Gain (Loss) [Line Items]
Concentration risk percentage	12.00%	20.00%
Interest Rate Contract, Fixed Rate
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, amount of hedged item	$ 50,000,000

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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+ References

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+ References

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The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

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