Business Combinations - Acquisitions Accounted for Business Combinations (Detail)	3 Months Ended
	Mar. 31, 2017 USD ($)
Business Combination, Separately Recognized Transactions [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	$ 701,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	490,000
Cash Paid	0
Business Acquisition Cost of Entity Note Payable	0
Other Payable	0
Recorded Earn-Out Payable	(211,000)
Net Assets Acquired	(211,000)
Maximum Potential Earn- Out Payable	0
Other current assets	93,000
Goodwill	429,000
Purchased customer accounts	(32,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	12,000
Deferred Tax Liabilities, Net	689,000
Other Acquisitions [Member]
Business Combination, Separately Recognized Transactions [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	701,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	490,000
Net Assets Acquired	(211,000)
Other current assets	93,000
Goodwill	429,000
Purchased customer accounts	(32,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other	12,000
Deferred Tax Liabilities, Net	689,000
Other Acquisitions [Member] | Various
Business Combination, Separately Recognized Transactions [Line Items]
Cash Paid	0
Business Acquisition Cost of Entity Note Payable	0
Other Payable	0
Recorded Earn-Out Payable	(211,000)
Net Assets Acquired	(211,000)
Maximum Potential Earn- Out Payable	$ 0