Goodwill and Intangible Assets - Summary of Goodwill and Intangible Assets Acquired (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 4,401	$ 4,401
Accumulated Amortization	(1,516)	(1,394)
Net Carrying Value	2,885	3,007
Lease Related Intangibles [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	3,621	3,621
Accumulated Amortization	(942)	(825)
Net Carrying Value	2,679	2,796
Non-Compete Agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	30	30
Accumulated Amortization	(17)	(16)
Net Carrying Value	13	14
Trade Names [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	750	750
Accumulated Amortization	(557)	(553)
Net Carrying Value	$ 193	$ 197

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, resulting from a business combination.

+ References

No definition available.

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- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph ((a)(1),(b))

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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