Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues
Rental	$ 390,013	$ 351,790	$ 353,889
Rental related services	98,061	92,393	101,038
Rental operations	488,074	444,183	454,927
Revenues	128,759	128,371	115,303
Total revenues	616,833	572,554	570,230
Direct costs of rental operations:
Depreciation of rental equipment	91,887	85,866	80,391
Rental related services	74,256	68,105	76,241
Other	91,069	73,818	79,365
Total direct costs of rental operations	257,212	227,789	235,997
Costs of sales	78,600	81,019	68,068
Total costs of revenues	335,812	308,808	304,065
Gross profit	281,021	263,746	266,165
Selling and administrative expenses	148,600	122,993	124,793
Income from operations	132,421	140,753	141,372
Other income (expense):
Interest expense	(10,455)	(8,787)	(12,331)
Foreign currency exchange (loss) gain	(210)	78	84
Income before provision for income taxes	121,756	132,044	129,125
Provision for income taxes	32,051	30,060	32,319
Net income	$ 89,705	$ 101,984	$ 96,806
Earnings per share:
Basic	$ 3.70	$ 4.22	$ 3.99
Diluted	$ 3.66	$ 4.16	$ 3.93
Shares used in per share calculation:
Basic	24,220	24,157	24,250
Diluted	24,515	24,531	24,623
Cash dividends declared per share	$ 1.74	$ 1.68	$ 1.50
Sales [Member]
Revenues
Revenues	$ 125,235	$ 124,604	$ 110,229
Other [Member]
Revenues
Revenues	$ 3,524	$ 3,767	$ 5,074