Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2018

Accounting Policies [Abstract]

Allowance for Doubtful Accounts Receivable

Additions, deductions and balances for allowance for doubtful accounts for 2018, 2017 and 2016 are as follows (in thousands):

	2018		2017		2016
Balance at beginning of year	$	2,300	$	2,156	$	2,046
Additions:
Charged to costs and expense	2,855		3,141		2,427
Recovery of previous write-offs	1,215		1,122		1,395
Uncollectible receivables written off	4,300		4,119		3,712
Balance at end of year	$	2,070	$	2,300	$	2,156