Derivative Financial Instruments - Fair value gains and losses on derivative financial instruments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Summary of the fair value gains and losses on derivative financial instruments
Net fair value gains (losses) on derivative financial instrument	$ 16	$ 207
Realized gains/(losses) on derivatives	(275)	700
Interest rate lock commitments
Summary of the fair value gains and losses on derivative financial instruments
Net fair value gains (losses) on derivative financial instrument	19	252
Forward Commitments
Summary of the fair value gains and losses on derivative financial instruments
Net fair value gains (losses) on derivative financial instrument	8	$ (45)
Customer derivatives - Interest rate swaps
Summary of the fair value gains and losses on derivative financial instruments
Net fair value gains (losses) on derivative financial instrument	$ (11)

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.

No definition available.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(h))
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

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