Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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- Definition

Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
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The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings.

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DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES - Derivative Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Mar. 31, 2019
Derivative [Line Items]
Notional Amount	$ 499,142		$ 499,142		$ 182,239
Estimated Fair Value Asset (Liability)	(2,073)		(2,073)		811
Designated as hedging instrument \| Cash flow hedges
Derivative [Line Items]
Notional Amount	140,000		140,000		$ 90,000
Weighted Average Maturity (in years)
Estimated Fair Value Asset (Liability)	(2,090)		(2,090)		$ 803
Designated as hedging instrument \| Cash flow hedges \| Interest rate cap agreements
Derivative [Line Items]
Notional Amount	90,000		$ 90,000		$ 90,000
Weighted Average Maturity (in years)			3 years 4 months 24 days		4 years 1 month 6 days
Estimated Fair Value Asset (Liability)	89		$ 89		$ 803
Realized gain (loss)	(183)	$ (137)	(521)	$ (367)
Designated as hedging instrument \| Cash flow hedges \| Interest rate swap on deposits
Derivative [Line Items]
Notional Amount	50,000		$ 50,000			$ 50,000
Weighted Average Maturity (in years)			4 years 6 months
Estimated Fair Value Asset (Liability)	(2,179)		$ (2,179)
Realized gain (loss)	17	0	17	0
Designated as hedging instrument \| Economic hedges
Derivative [Line Items]
Notional Amount	7,762		7,762
Estimated Fair Value Asset (Liability)	(61)		(61)
Designated as hedging instrument \| Economic hedges \| Forward sale commitments
Derivative [Line Items]
Notional Amount	7,762		$ 7,762
Weighted Average Maturity (in years)			1 month 6 days
Estimated Fair Value Asset (Liability)	(61)		$ (61)
Realized gain (loss)	(31)	43	(61)	190
Not designated as hedging instrument
Derivative [Line Items]
Notional Amount	351,380		351,380		92,239
Estimated Fair Value Asset (Liability)	78		78		8
Not designated as hedging instrument \| Interest rate lock commitments
Derivative [Line Items]
Notional Amount	12,242		$ 12,242		$ 957
Weighted Average Maturity (in years)			1 month 6 days		1 month 6 days
Estimated Fair Value Asset (Liability)	78		$ 78		$ 8
Realized gain (loss)	7	$ 0	70	$ 9
Not designated as hedging instrument \| Customer loan derivative liability
Derivative [Line Items]
Notional Amount	169,569		$ 169,569		$ 45,641
Weighted Average Maturity (in years)			9 years 9 months 18 days		9 years 10 months 24 days
Estimated Fair Value Asset (Liability)	(10,923)		$ (10,923)		$ (1,353)
Not designated as hedging instrument \| Customer loan derivative asset
Derivative [Line Items]
Notional Amount	169,569		$ 169,569		$ 45,641
Weighted Average Maturity (in years)			9 years 9 months 18 days		9 years 10 months 24 days
Estimated Fair Value Asset (Liability)	$ 10,923		$ 10,923		$ 1,353