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Fair Value (Fair Value Measurement and Assumptions) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Assets:
Impaired Loans	$ 46,706	$ 14,306
Assumptions used in discounted cash flow model to determine fair value of investments classified within level 3
Charges to allowance for probable loan losses in connection with other real estate owned	51	170
Adjustment to fair value in connection with other real estate owned	8	3,071
Impaired commercial collateral dependent loans	46,706	14,306
Impaired commercial collateral dependent receivables appraisals to determine fair value within immediately preceding twelve months	33,889	10,911
Impaired collateral dependent commercial loans with internal evaluation completed within last twelve months	9,407	0
Measured on a non-recurring basis
Assumptions used in discounted cash flow model to determine fair value of investments classified within level 3
Change in net provision, impaired loans	9,510	356
Change in net provision, other real estate owned	8	3,071
Measured on a non-recurring basis | Significant Unobservable Inputs (Level 3)
Assets:
Impaired Loans	34,552	1,563
Non-financial assets:
Other real estate owned	3	38,871
Assumptions used in discounted cash flow model to determine fair value of investments classified within level 3
Impaired commercial collateral dependent loans	34,552	1,563
Measured on a non-recurring basis | Assets/liabilities measured at fair value
Assets:
Impaired Loans	34,552	1,563
Non-financial assets:
Other real estate owned	3	38,871
Assumptions used in discounted cash flow model to determine fair value of investments classified within level 3
Impaired commercial collateral dependent loans	$ 34,552	$ 1,563

X

- Definition

Amount of increase (decrease) of allowance reserve for credit losses in connection with loans transferred to other real estate owned.

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- Definition

Reflects the amount of charge-off related to a loan prior to foreclosure.

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The estimated fair value of recorded investment related to change in provision for impaired financing receivables measured at fair value.

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Carrying amount as of the balance sheet date of change in Provision of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

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The impaired collateral dependent commercial loans where an internal evaluation has been done in the last twelve months.

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Represents the impaired commercial collateral dependent financing receivables where the basis for fair value is an appraisal obtained in the last twelve months.

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The estimated fair value of the recorded impaired collateral measured on a non-recurring basis as of the reporting date.

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Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

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