Fair Value Measurements - Valuation of Financial Instruments That are Marked-to-Market on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Assets
Estimated Fair Value	$ 614,582	$ 487,669
Total earning assets	1,754,833
Fair Value Measurements on a Recurring Basis
Assets
Estimated Fair Value	614,582	487,669
Derivative instruments	3,653	715
Total earning assets	618,235	488,384
Liabilities
Derivative instruments	(275)	(1,164)
Fair Value Measurements on a Recurring Basis \| Level 1
Assets
Estimated Fair Value	0	0
Derivative instruments	0	0
Total earning assets	0	0
Liabilities
Derivative instruments	0	0
Fair Value Measurements on a Recurring Basis \| Level 2
Assets
Estimated Fair Value	538,742	487,669
Derivative instruments	3,653	715
Total earning assets	542,395	488,384
Liabilities
Derivative instruments	(275)	(1,164)
Fair Value Measurements on a Recurring Basis \| Level 3
Assets
Estimated Fair Value	75,840	0
Derivative instruments	0	0
Total earning assets	75,840	0
Liabilities
Derivative instruments	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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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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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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