Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2015

Accounting Policies [Abstract]

Estimated Useful Lives and Residual Values of Company's Rental Equipment

The estimated useful lives and residual values of the Company’s rental equipment used for financial reporting purposes are as follows:

Relocatable modular buildings	18 years, 50% residual value
Relocatable modular accessories	3 to 18 years, no residual value
Portable storage containers	25 years, 62.5% residual value
Electronic test equipment and accessories	1 to 8 years, no residual value
Liquid and solid containment tanks and boxes and accessories	10 to 20 years, no residual value

Property, Plant and Equipment

Property, plant and equipment consist of the following:

(dollar amounts in thousands)	Estimated useful life		December 31,
	in years		2015			2014
Land	Indefinite		$	40,378		$	38,455
Land improvements	20 – 50			42,004			39,715
Buildings		30		25,520			21,486
Furniture, office and computer equipment	3 – 10			34,053			32,544
Machinery and service equipment	5 – 20			28,642			24,454
				170,597			156,654
Less accumulated depreciation				(61,410	)		(53,503	)
				109,187			103,151
Construction in progress				566			5,477
			$	109,753		$	108,628

Weighted-Average Common Stock Used to Calculate Basic and Diluted Earnings per Share

The table below presents the weighted-average common stock used to calculate basic and diluted earnings per share:

(in thousands)	Year Ended December 31,
	2015		2014		2013
Weighted-average common stock for calculating basic    earnings per share		25,369		25,914		25,433
Effect of potentially dilutive securities from equity-based    compensation		88		261		493
Weighted-average common stock for calculating diluted    earnings per share		25,457		26,175		25,926

Securities Not Included in Computation of Diluted Earnings Per Share

The following securities were not included in the computation of diluted earnings per share as their effect would have been anti-dilutive:

(in thousands)	Year Ended December 31,
	2015		2014		2013
Options to purchase common stock		746		9		20

Summary of Share Repurchase Activities

The following table presents share repurchase activities during the years ended December 31, 2015 and 2014:

	Year ended December 31
(in thousands, except share and per share amounts)	2015		2014
Number of shares repurchased		2,407,974		—
Aggregate purchase price	$	63,953		—
Average price per repurchased shares	$	26.56		—

Summary of Allowance for Doubtful Accounts Activity

The allowance for doubtful accounts activity was as follows:

(in thousands)	2015			2014
Beginning balance, January 1	$	2,038		$	2,007
Provision for doubtful accounts		2,149			1,825
Write-offs, net of recoveries		(2,100	)		(1,794	)
Ending balance, December 31	$	2,087		$	2,038