Goodwill and Other Intangible Assets, Net of Accumulated Amortization - Components of Other Intangible Assets (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Schedule of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]
Below market leases, Gross Amount	$ 15	$ 15
Definite life, Accumulated Amortization	(11,458)	(9,934)
Below market leases, Accumulated Amortization	(14)	(13)
Below market leases. Net Carrying Amount	$ 1	$ 2
Definite life, Weighted- Average Remaining Life (Years)	4 years 7 months 6 days	5 years
Gross Amount	$ 37,354	$ 34,855
Net Carrying Amount	25,896	24,921
Trademark and Trade Names [Member]
Schedule of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]
Definite life, Gross Amount	7,061	7,061
Definite life, Accumulated Amortization	(6,183)	(6,030)
Definite life, Net Carrying Amount	$ 878	$ 1,031
Definite life, Weighted- Average Remaining Life (Years)	1 month 6 days	2 months 12 days
Non-contractual Customers [Member]
Schedule of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]
Definite life, Gross Amount	$ 10,447	$ 7,950
Definite life, Accumulated Amortization	(2,407)	(1,495)
Definite life, Net Carrying Amount	$ 8,040	$ 6,455
Definite life, Weighted- Average Remaining Life (Years)	2 years 6 months	2 years 6 months
License Agreements (GSE) [Member]
Schedule of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]
Definite life, Gross Amount	$ 4,981	$ 4,981
Definite life, Accumulated Amortization	(1,548)	(1,298)
Definite life, Net Carrying Amount	$ 3,433	$ 3,683
Definite life, Weighted- Average Remaining Life (Years)	8 months 12 days	10 months 24 days
Non-compete Agreements [Member]
Schedule of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]
Definite life, Gross Amount	$ 3,608	$ 3,606
Definite life, Accumulated Amortization	(642)	(496)
Definite life, Net Carrying Amount	$ 2,966	$ 3,110
Definite life, Weighted- Average Remaining Life (Years)	1 year 1 month 6 days	1 year 2 months 12 days
Contractual Customers [Member]
Schedule of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]
Definite life, Gross Amount	$ 1,452	$ 1,452
Definite life, Accumulated Amortization	(664)	(602)
Definite life, Net Carrying Amount	$ 788	$ 850
Definite life, Weighted- Average Remaining Life (Years)	2 months 12 days	2 months 12 days
Trademark and Trade Names [Member]
Schedule of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]
Indefinite life, intangible assets	$ 4,400	$ 4,400
License Agreements (GSE) [Member]
Schedule of Acquired Finite And Indefinite Lived Intangible Asset By Major Class [Line Items]
Indefinite life, intangible assets	$ 5,390	$ 5,390