Stock-based Compensation - Compensation Expense Associated with Performance Units (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense	$ 750,000
Performance Shares [Member] | Year Twenty Twenty One [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense	1,806,000
Performance Shares [Member] | Year Twenty Twenty [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense	275,000	$ 206,000
Performance Shares [Member] | Year Twenty Nineteen [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense	3,319,000	3,319,000	$ 2,489,000
Performance Shares [Member] | Year Twenty Eighteen [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense	$ 667,000	2,668,000	2,668,000
Performance Shares [Member] | Year Twenty Seventeen [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense		$ 642,000	1,927,000
Performance Shares [Member] | Year Twenty Sixteen [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense			$ 321,000