CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Statement Of Financial Position [Abstract]
Allowance for credit losses, net	$ 10
Held-to-maturity securities, fair value	$ 205,458	$ 208,852
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	124,131,401	125,173,597
Common stock, shares outstanding	124,131,401	125,173,597