Changes in Accumulated Other Comprehensive Income by Component - Reclassification Adjustments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Tax benefit (expense)	$ (6,592)	$ (2,736)
Net income	20,190	9,156
Realized Gains (Losses) on Sale of Available-for-sale Securities \| Amounts Reclassified from Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
(Losses) gains from the sale of available-for-sale securities	(11)	4
Tax benefit (expense)	2	(1)
Net income	$ (9)	$ 3

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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