Goodwill and Other Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Finite-lived Intangible Assets [Roll Forward]
CDI and CRI Balance, beginning of period	$ 119,497	$ 119,497	$ 119,497	$ 119,497	$ 119,497
Accumulated Amortization, beginning of period	(67,247)	(62,377)	(46,217)	(62,377)	(39,871)
Amortization	(4,870)	(4,870)	(5,587)	(9,740)	(11,933)
CDI and CRI Balance, end of period	119,497	119,497	119,497	119,497	119,497
Accumulated Amortization, end of period	(72,117)	(67,247)	(51,804)	(72,117)	(51,804)
Net CDI and CRI, end of period	$ 47,380	$ 52,250	$ 67,693	$ 47,380	$ 67,693

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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-Publisher FASB
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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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