Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (2,237,285)	$ 140,981
Other comprehensive income, net of tax:
Net unrealized gains arising during period from debt securities available for sale	99,699	51,700
Less: reclassification adjustment for net gains on sale of debt securities available for sale in net income	14,572	6,834
Net change in net unrealized holding gains on debt securities available for sale	85,127	44,866
Change in unamortized net holding gains on debt securities held to maturity	1,575	1,743
Change in unamortized non-credit related impairment on debt securities held to maturity	118	368
Net change in unamortized holding gains on debt securities held to maturity	1,693	2,111
Unrealized holding gains arising during period from cash flow hedge instruments	274,837	24,053
Change in defined benefit plans	1,754	3,119
Other comprehensive income, net of tax	363,411	74,149
Comprehensive (loss) income	(1,873,874)	215,130
Less: comprehensive income attributable to noncontrolling interests	501	556
Comprehensive (loss) income attributable to BBVA USA Bancshares, Inc.	$ (1,874,375)	$ 214,574