Condensed Parent Company Information - Condensed Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Condensed Financial Statements, Captions [Line Items]
Interest expense	$ (19,562)	$ (33,903)	$ (23,777)
Net income	81,477	92,046	89,289
Parent Company
Condensed Financial Statements, Captions [Line Items]
Dividends from wholly-owned subsidiaries	63,100	29,800	15,525
Earnings of wholly-owned subsidiaries, net of dividends	20,899	65,555	77,050
Interest expense	(1,743)	(2,648)	(2,498)
All other income and expenses, net	(779)	(661)	(788)
Net income	$ 81,477	$ 92,046	$ 89,289