Summary of Significant Accounting Policies (Revised Consolidated Statements of Cash Flows) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 4,082	$ 98
Depreciation and amortization	6,240	5,577
Deferred taxes		68
Inventory (increase) decrease	1,616	(3,986)
Prepaid expenses and prepaid income taxes decrease (increase)	344	149
Net cash (used in) provided by operating activities	8,275	(3,746)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of rental equipment, property and other equipment	(6,679)	(9,230)
Net cash used in investing activities	(6,665)	(9,248)
Net change in cash and cash equivalents	$ 1,459	(12,636)
As Reported
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income		357
Depreciation and amortization		5,558
Deferred taxes		157
Inventory (increase) decrease		(4,468)
Prepaid expenses and prepaid income taxes decrease (increase)		202
Net cash (used in) provided by operating activities		(3,846)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of rental equipment, property and other equipment		(9,130)
Net cash used in investing activities		(9,148)
Net change in cash and cash equivalents		(12,636)
Revisions \| Revision Of Prior Period Financial Statements
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income		(259)
Depreciation and amortization		19
Deferred taxes		(89)
Inventory (increase) decrease		482
Prepaid expenses and prepaid income taxes decrease (increase)		(53)
Net cash (used in) provided by operating activities		100
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of rental equipment, property and other equipment		(100)
Net cash used in investing activities		(100)
Net change in cash and cash equivalents		$ 0

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