Long-Term Debt and Short-Term Borrowings - Schedule of Long-Term Debt and Short-Term Borrowings (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Total long-term debt	$ 1,773,396	$ 1,784,921
Less: current maturities of long-term debt	(1,814)	(3,146)
Less: unamortized debt issuance costs	(10,337)	(14,515)
Total long-term debt, net of current maturities	1,761,245	1,767,260
Warehouse lines of credit (which fund loans that U.S. Government Sponsored Enterprises have committed to purchase)	977,175	1,328,761
Other	4,534
Total short-term borrowings	981,709	1,328,761
Warehouse Agreement Borrowings [Member]
Debt Instrument [Line Items]
Warehouse lines of credit (which fund loans that U.S. Government Sponsored Enterprises have committed to purchase)	977,175	1,328,761
Senior secured term loans [Member]
Debt Instrument [Line Items]
Total long-term debt	748,531	758,452
Other Long Term Debt [Member]
Debt Instrument [Line Items]
Total long-term debt	1,861	3,682
4.875% Senior Notes [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Total long-term debt	597,052	596,653
5.25% Senior Notes [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Total long-term debt	425,952	426,134
Pricing at daily one-month LIBOR plus 1.30%, maturing October 21, 2019 [Member] \| Warehouse Agreement Borrowings [Member]
Debt Instrument [Line Items]
Warehouse lines of credit (which fund loans that U.S. Government Sponsored Enterprises have committed to purchase)	$ 977,175	$ 1,328,761

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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