Debt Securities Available for Sale and Debt Securities Held to Maturity - Interest Income Attributable to Debt Securities Available for Sale (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Interest Income on Debt Securities Available For Sale by Taxable Status
Total Interest Income	$ 54,574	$ 33,278	$ 26,573
Debt securities available for sale
Interest Income on Debt Securities Available For Sale by Taxable Status
Taxable interest income	37,436	18,382	16,238
Tax-exempt interest income	17,138	14,896	10,335
Total Interest Income	$ 54,574	$ 33,278	$ 26,573

Amount of interest income, amortization of premium and accretion of discount on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale); classified as operating.

No definition available.

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- Definition

Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities exempt from state, federal and other income tax.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.2)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

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Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities subject to state, federal and other income tax.

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- Definition

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.

+ References

No definition available.

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