Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount, before tax, of unrealized gain (loss) in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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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Significant Accounting Policies - Schedule of Reclassification of Debt Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Amortized cost	$ 940,765		$ 882,872
Securities available-for-sale (at fair value)	946,855		865,831
Accounting Standards Update 2017-12
Debt Securities, Available-for-sale [Line Items]
Amortized cost		$ 53,526
Net unrealized gain (loss) reflected in OCI		(730)
Securities available-for-sale (at fair value)		52,796
Private mortgage-backed securities and collateralized mortgage obligations \| Accounting Standards Update 2017-12
Debt Securities, Available-for-sale [Line Items]
Amortized cost		21,526
Net unrealized gain (loss) reflected in OCI		147
Securities available-for-sale (at fair value)		21,673
Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
Amortized cost	239,364		212,807
Securities available-for-sale (at fair value)	$ 238,218		$ 209,366
Collateralized loan obligations \| Accounting Standards Update 2017-12
Debt Securities, Available-for-sale [Line Items]
Amortized cost		32,000
Net unrealized gain (loss) reflected in OCI		(877)
Securities available-for-sale (at fair value)		$ 31,123