Nature of Operations and Significant Accounting Policies - Organization (Details)	9 Months Ended
Sep. 30, 2017 location
Denver, Colorado
Organization
Number of branches	7
Boulder, Colorado
Organization
Number of branches	1
Vail, Colorado
Organization
Number of branches	1
Colorado Springs, Colorado
Organization
Number of branches	1
Fort Collins, Colorado
Organization
Number of branches	1
Phoenix, Arizona
Organization
Number of branches	4

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