Condensed Consolidated Statements of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues
Rental	$ 90,857	$ 82,155	$ 261,658	$ 233,683
Rental related services	30,816	23,880	76,738	60,797
Rental operations	121,673	106,035	338,396	294,480
Revenues			84,613	70,735
Total revenues	173,562	143,147	423,009	365,215
Direct costs of rental operations:
Depreciation of rental equipment	20,535	18,407	59,222	54,287
Rental related services	23,007	18,618	57,507	47,404
Other	19,654	17,674	61,128	52,696
Total direct costs of rental operations	63,196	54,699	177,857	154,387
Costs of sales	32,084	24,398	49,984	42,680
Total costs of revenues	95,280	79,097	227,841	197,067
Gross profit	78,282	64,050	195,168	168,148
Selling and administrative expenses	31,534	28,226	92,044	85,833
Income from operations	46,748	35,824	103,124	82,315
Other income (expense):
Interest expense	(3,161)	(3,142)	(9,407)	(9,133)
Foreign currency exchange loss	(132)	(129)	(46)	(505)
Income before provision for income taxes	43,455	32,553	93,671	72,677
Provision for income taxes	10,987	7,774	23,266	17,520
Net income	$ 32,468	$ 24,779	$ 70,405	$ 55,157
Earnings per share:
Basic	$ 1.34	$ 1.03	$ 2.90	$ 2.29
Diluted	$ 1.32	$ 1.01	$ 2.86	$ 2.25
Shares used in per share calculation:
Basic	24,268	24,172	24,237	24,128
Diluted	24,632	24,563	24,592	24,550
Cash dividends declared per share	$ 0.375	$ 0.340	$ 1.125	$ 1.020
Sales [Member]
Revenues
Revenues	$ 50,855	$ 36,085	$ 81,387	$ 67,722
Other [Member]
Revenues
Revenues	$ 1,034	$ 1,027	$ 3,226	$ 3,013