Deposits - Components of interest expense and other information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Banking and Thrift [Abstract]
Money market and other	$ 43,252	$ 31,856	$ 21,136
Savings deposits	1,889	1,354	1,282
Time deposits	89,817	41,692	25,673
Interest on deposits	$ 134,958	$ 74,902	$ 48,091

No definition available.

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- Definition

Aggregate amount of interest expense on all deposits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.6)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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- Definition

Interest expense incurred on all money market deposits.

+ References

+ Details

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- Definition

Interest expense incurred on all savings account deposits.

+ References

+ Details

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- Definition

The aggregate interest expense incurred on time deposits, including certificates of deposits, in domestic offices.

+ References

+ Details

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