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.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 20
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Balance Type:	debit
Period Type:	duration

- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
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- Details

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Namespace Prefix:
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- Details

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Goodwill - Narrative (Details) - USD ($)		12 Months Ended
Goodwill - Narrative (Details) - USD ($)	May 19, 2017	Dec. 31, 2018	Dec. 31, 2017	Jul. 14, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Goodwill		$ 445,355,000	$ 445,355,000		$ 244,000,000
Measurement period adjustment			(469,000)
Goodwill impairment loss		$ 0	$ 0
IAB
Business Acquisition [Line Items]
Goodwill				$ 153,636,000
Arlington Bank
Business Acquisition [Line Items]
Goodwill	$ 47,719,000
Measurement period adjustment	$ 469,000