Fair Value Measurements - Schedule of Fair Value Information for Financial Assets and Liabilities Carried on Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Financial Liabilities:
Revolving credit facility	$ 15,000	$ 15,000
Total long-term debt	45,295	45,504
Carrying Value [Member]
Financial Liabilities:
Revolving credit facility	15,000	15,000
Total long-term debt	45,269	45,473
Carrying Value [Member] | 4.25% Convertible Senior Notes [Member]
Financial Liabilities:
Total long-term debt	23,916	23,885
Carrying Value [Member] | 3.90% Promissory Note [Member]
Financial Liabilities:
Total long-term debt	9,203	9,287
Carrying Value [Member] | 3.75% Callable Promissory Note
Financial Liabilities:
Total long-term debt	7,063	7,153
Carrying Value [Member] | 4.55% Promissory Note [Member]
Financial Liabilities:
Total long-term debt	5,087	5,148
Estimate of Fair Value Measurement [Member]
Financial Liabilities:
Revolving credit facility	15,000	15,000
Total long-term debt	49,085	57,639
Estimate of Fair Value Measurement [Member] | (Level 2) [Member]
Financial Liabilities:
Revolving credit facility	15,000	15,000
Total long-term debt	27,111	33,248
Estimate of Fair Value Measurement [Member] | (Level 3) [Member]
Financial Liabilities:
Total long-term debt	21,974	24,391
Estimate of Fair Value Measurement [Member] | 4.25% Convertible Senior Notes [Member]
Financial Liabilities:
Total long-term debt	27,111	33,248
Estimate of Fair Value Measurement [Member] | 4.25% Convertible Senior Notes [Member] | (Level 2) [Member]
Financial Liabilities:
Total long-term debt	27,111	33,248
Estimate of Fair Value Measurement [Member] | 3.90% Promissory Note [Member]
Financial Liabilities:
Total long-term debt	9,455	10,488
Estimate of Fair Value Measurement [Member] | 3.90% Promissory Note [Member] | (Level 3) [Member]
Financial Liabilities:
Total long-term debt	9,455	10,488
Estimate of Fair Value Measurement [Member] | 3.75% Callable Promissory Note
Financial Liabilities:
Total long-term debt	7,132	7,852
Estimate of Fair Value Measurement [Member] | 3.75% Callable Promissory Note | (Level 3) [Member]
Financial Liabilities:
Total long-term debt	7,132	7,852
Estimate of Fair Value Measurement [Member] | 4.55% Promissory Note [Member]
Financial Liabilities:
Total long-term debt	5,387	6,051
Estimate of Fair Value Measurement [Member] | 4.55% Promissory Note [Member] | (Level 3) [Member]
Financial Liabilities:
Total long-term debt	$ 5,387	$ 6,051