v2.4.1.9

Quarterly financial data (unaudited) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Mar. 31, 2013 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Quarterly financial data (unaudited) |  |  |  |  |  |  |  |  |  |  |
Revenue | $ 33,627 us-gaap_SalesRevenueNet | $ 30,822 us-gaap_SalesRevenueNet | $ 28,396 us-gaap_SalesRevenueNet | $ 26,452 us-gaap_SalesRevenueNet | $ 28,766 us-gaap_SalesRevenueNet | $ 28,607 us-gaap_SalesRevenueNet | $ 26,239 us-gaap_SalesRevenueNet | $ 23,134 us-gaap_SalesRevenueNet | $ 119,297 us-gaap_SalesRevenueNet | $ 106,746 us-gaap_SalesRevenueNet | $ 102,506 us-gaap_SalesRevenueNet
(Loss) income from operations | (6,014)us-gaap_OperatingIncomeLoss | (3,487)us-gaap_OperatingIncomeLoss | (3,352)us-gaap_OperatingIncomeLoss | (5,173)us-gaap_OperatingIncomeLoss | (752)us-gaap_OperatingIncomeLoss | 784 us-gaap_OperatingIncomeLoss | (424)us-gaap_OperatingIncomeLoss | (1,502)us-gaap_OperatingIncomeLoss | (18,026)us-gaap_OperatingIncomeLoss | (1,894)us-gaap_OperatingIncomeLoss | 10,846 us-gaap_OperatingIncomeLoss
Net (loss) income attributable to common stockholders | $ (6,524)us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic | $ (3,815)us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic | $ (3,734)us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic | $ (5,448)us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic | $ (2,802)us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic | $ 354 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic | $ (399)us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic | $ (1,121)us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic | $ (19,521)us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic | $ (3,968)us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic | $ 7,295 us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic
Basic (loss) earnings per share (in dollars per share) | $ (0.18)us-gaap_EarningsPerShareBasic | $ (0.11)us-gaap_EarningsPerShareBasic | $ (0.10)us-gaap_EarningsPerShareBasic | $ (0.15)us-gaap_EarningsPerShareBasic | $ (0.08)us-gaap_EarningsPerShareBasic | $ 0.01 us-gaap_EarningsPerShareBasic | $ (0.01)us-gaap_EarningsPerShareBasic | $ (0.03)us-gaap_EarningsPerShareBasic | $ (0.55)us-gaap_EarningsPerShareBasic | $ (0.11)us-gaap_EarningsPerShareBasic | $ 0.21 us-gaap_EarningsPerShareBasic
Diluted (loss) earnings per share (in dollars per share) | $ (0.18)us-gaap_EarningsPerShareDiluted | $ (0.11)us-gaap_EarningsPerShareDiluted | $ (0.10)us-gaap_EarningsPerShareDiluted | $ (0.15)us-gaap_EarningsPerShareDiluted | $ (0.08)us-gaap_EarningsPerShareDiluted | $ 0.01 us-gaap_EarningsPerShareDiluted | $ (0.01)us-gaap_EarningsPerShareDiluted | $ (0.03)us-gaap_EarningsPerShareDiluted | $ (0.55)us-gaap_EarningsPerShareDiluted | $ (0.11)us-gaap_EarningsPerShareDiluted | $ 0.20 us-gaap_EarningsPerShareDiluted

X
- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1252-109256 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 55 -Paragraph 52 -URI http://asc.fasb.org/extlink&oid=32703322&loc=d3e4984-109258 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.21) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.19) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.23) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 18 -Article 7 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 20 -Article 5 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 21 -Article 9 + Details
Name: | us-gaap_EarningsPerShareBasic
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1252-109256 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.21) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 18 -Article 7 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 20 -Article 5 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 21 -Article 9 + Details
Name: | us-gaap_EarningsPerShareDiluted
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1377-109256 + Details
Name: | us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The net result for the period of deducting operating expenses from operating revenues. + References No definition available. + Details
Name: | us-gaap_OperatingIncomeLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_QuarterlyFinancialInformationDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Article 5 + Details
Name: | us-gaap_SalesRevenueNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration