STOCKHOLDERS' EQUITY - Changes to Accumulate Other Comprehensive Income by Components (Detail) - Gain (loss) on securities available-for-sale - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance at beginning of period	$ (24,117)	$ 5,227
Unrealized gain (loss) arising during the period	8,746	(19,682)
Reclassification adjustment from other comprehensive income	(208)	(5,241)
Tax effect of current period changes	(2,512)	7,658
Total changes, net of taxes	6,026	(17,265)
Reclassification of stranded tax effects to retained earnings	0	496
Balance at end of period	$ (18,091)	$ (11,542)

Tax Cuts And Jobs Act Of 2017, Reclassification From AOCI To Retained Earnings, Tax Effect

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Amount before tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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