Schedule I - Condensed Statements of Cash Flows (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash Flows From Operating Activities:
Net income (loss)	$ 44,788	$ (202,386)	$ (12,531)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Net cash (used in) provided by operating activities	293,935	192,457	280,412
Cash Flows From Investing Activities:
Net cash (used in) provided by investing activities	(180,029)	(170,873)	(160,518)
Cash Flows From Financing Activities:
Exercise of stock options	4,282	11	82
Dividends paid to common stockholders	(325)	(1,544)	(65,306)
Net cash provided by (used in) financing activities	(112,896)	(56,965)	(70,139)
Change in Cash and Cash Equivalents, including Restricted Cash	1,010	(35,381)	49,755
Cash and Cash Equivalents, including Restricted Cash—Beginning of year	33,997	69,378	19,623
Cash and Cash Equivalents, including Restricted Cash—End of year	35,007	33,997	69,378
Supplemental Disclosures of Noncash Investing and Financing Activities
Dividends declared, but unpaid	84	470	908
Parent Company [Member]
Cash Flows From Operating Activities:
Net income (loss)	44,788	(202,386)	(12,531)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Equity in net (income) loss of subsidiary	(44,788)	202,386	12,531
Dividends (forfeited) received from subsidiary-return on capital, net of forfeitures		(31)	26,412
Net cash (used in) provided by operating activities		(31)	26,412
Cash Flows From Investing Activities:
Dividends (forfeited) received from subsidiary- return of capital, net of forfeitures	(61)	1,137	39,372
Capital contributed to subsidiary from exercises of stock options	(4,230)
Net cash (used in) provided by investing activities	(4,291)	1,137	39,372
Cash Flows From Financing Activities:
Exercise of stock options	4,282
Dividends paid to common stockholders	(325)	(1,544)	(65,306)
Net cash provided by (used in) financing activities	3,957	(1,544)	(65,306)
Change in Cash and Cash Equivalents, including Restricted Cash	(334)	(438)	478
Cash and Cash Equivalents, including Restricted Cash—Beginning of year	470	908	430
Cash and Cash Equivalents, including Restricted Cash—End of year	136	470	908
Supplemental Disclosures of Noncash Investing and Financing Activities
Dividends from subsidiary- return of capital, for purchase of treasury stock	98,032
Dividends declared, but unpaid	$ 84	$ 470	$ 908