Goodwill and Other Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 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
Fully amortized portion	(1,924)	0	0	(1,924)	0
CDI and CRI Balance, end of period	117,573	119,497	119,497	117,573	119,497
Accumulated Amortization, beginning of period	(72,117)	(67,247)	(51,804)	(62,377)	(39,871)
Amortization	(4,833)	(4,870)	(5,587)	(14,573)	(17,520)
Fully amortized portion	1,924	0	0	1,924	0
Accumulated Amortization, end of period	(75,026)	(72,117)	(57,391)	(75,026)	(57,391)
Net CDI and CRI, end of period	42,547	47,380	62,106	42,547	62,106
CDI and CRI [Member]
Finite-lived Intangible Assets [Roll Forward]
Fully amortized portion	(1,924)	0	0	(1,924)	0
Fully amortized portion	$ 1,924	$ 0	$ 0	$ 1,924	$ 0

Finite Lived Intangible Assets Fully Amortized Portion

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- Definition

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.

+ References

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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
-Name Accounting Standards Codification
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- Definition

Amount before 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
-Name Accounting Standards Codification
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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

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

+ References

No definition available.

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