Detail of Certain Balance Sheet Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Activity in allowance for doubtful accounts
Balance at beginning of year	$ 4,379	$ 4,460	$ 6,333
Additions for bad debt expense	1,552	1,275	19
Deductions for uncollectible receivables written off, net of recoveries	(798)	(1,650)	(1,892)
Allowance for doubtful accounts of acquired companies at date of acquisition	25	294
Balance at end of year	5,158	4,379	$ 4,460
Other current liabilities
Accrued warranty costs	7,746	7,227
Accrued job losses	1,365	1,329
Accrued rent and lease obligations	891	953
Accrued sales and use tax	2,216	1,945
Deferred revenue	2,175	1,538
Liabilities due to former owners	2,650	520
Other current liabilities	11,634	11,001
Total other current liabilities	$ 28,677	$ 24,513