| **Variable Interest Entities**         | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               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| **Noncontrolling Interest [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            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| Variable Interest Entities             | Variable Interest EntitiesWe have entered into several arrangements under the NMTC program with US Bancorp to help fund a $59.3 million project to extend terrestrial broadband service for the first time to rural Northwestern Alaska communities via a high capacity hybrid fiber optic and microwave network.  When completed, the project, called TERRA-Northwest (“TERRA-NW”), will connect to the TERRA-Southwest (“TERRA-SW”) network and provide a high capacity backbone connection from the served communities to the Internet.  The NMTC program was provided for in the Community Renewal Tax Relief Act of 2000 (the “Act”) to induce capital investment in qualified lower income communities.  The Act permits taxpayers to claim credits against their federal income taxes for up to 39% of qualified investments in the equity of community development entities (“CDEs”).  CDEs are privately managed investment institutions that are certified to make qualified low-income community investments.On August 30, 2011, we entered into the first arrangement (“NMTC #1”).  In connection with the NMTC #1 transaction we loaned $58.3 million to TIF, a special purpose entity created to effect the financing arrangement, at 1% interest due August 30, 2041.  Simultaneously, US Bancorp invested $22.4 million in TIF.  TIF then contributed US Bancorp’s contribution and the loan proceeds to certain CDEs.  The CDEs, in turn, loaned the $76.8 million in funds less payment of placement fees, at interest rates varying from 1% to 3.96%, to Unicom, as partial financing for TERRA-NW. On October 3, 2012, we entered into the second arrangement (“NMTC #2”).  In connection with the NMTC #2 transaction we loaned $37.7 million to TIF 2 and TIF 2-USB, special purpose entities created to effect the financing arrangement, at 1% interest due October 2, 2042.  Simultaneously, US Bancorp invested $17.5 million in TIF 2 and TIF 2-USB.  TIF 2 and TIF 2-USB then contributed US Bancorp’s contributions and the loan proceeds to certain CDEs.  The CDEs, in turn, loaned the $55.2 million in funds less payment of placement fees, at interest rates varying from 0.7099% to 0.7693%, to Unicom, as partial financing for TERRA-NW.On December 11, 2012, we entered into the third arrangement (“NMTC #3”).  In connection with the NMTC #3 transaction we loaned $8.2 million to TIF 3, a special purpose entity created to effect the financing arrangement, at 1% interest due December 10, 2042.  Simultaneously, US Bancorp invested $3.8 million in TIF 3.  TIF 3 then contributed US Bancorp’s contributions and the loan proceeds to a CDE.  The CDE, in turn, loaned the $12.0 million in funds less payment of placement fees, at an interest rate of 1.35%, to Unicom, as partial financing for TERRA-NW. US Bancorp is the sole investor in TIF, TIF 2, TIF 2-USB and TIF 3, and as such, is entitled to substantially all of the benefits derived from the NMTCs.  All of the loan proceeds to Unicom, net of syndication and arrangement fees, are restricted for use on TERRA-NW.  Restricted cash of $1.1 million and $6.9 million was held by Unicom at December 31, 2014 and 2013, respectively, and is included in our Consolidated Balance Sheets.  We completed construction of TERRA-NW and placed the final phase into service in late 2014.These transactions include put/call provisions whereby we may be obligated or entitled to repurchase US Bancorp’s interests in TIF, TIF 2, TIF 2-USB and/or TIF 3. We believe that US Bancorp will exercise the put options in August 2018, October 2019 and December 2019, at the end of the compliance periods for NMTC #1, NMTC #2 and NMTC #3, respectively.  The NMTCs are subject to 100% recapture for a period of seven years as provided in the Internal Revenue Code.  We are required to be in compliance with various regulations and contractual provisions that apply to the NMTC arrangements.  Non-compliance with applicable requirements could result in projected tax benefits not being realized by US Bancorp.  We have agreed to indemnify US Bancorp for any loss or recapture of NMTCs until such time as our obligation to deliver tax benefits is relieved.  There have been no credit recaptures as of December 31, 2014.  The value attributed to the put/calls is nominal.We have determined that TIF, TIF 2, TIF 2-USB and TIF 3 are VIEs.  The consolidated financial statements of TIF, TIF 2, TIF 2-USB and TIF 3 include the CDEs discussed above.  The ongoing activities of the VIEs – collecting and remitting interest and fees and NMTC compliance – were all considered in the initial design and are not expected to significantly affect economic performance throughout the life of the VIEs.  Management considered the contractual arrangements that obligate us to deliver tax benefits and provide various other guarantees to US Bancorp; US Bancorp’s lack of a material interest in the underlying economics of the project; and the fact that we are obligated to absorb losses of the VIEs.  We concluded that we are the primary beneficiary of each and consolidated the VIEs in accordance with the accounting standard for consolidation.US Bancorp’s contributions, net of syndication fees and other direct costs incurred in structuring the NMTC arrangements, are included in Non-controlling Interests on the Consolidated Balance Sheets.  Incremental costs to maintain the structure during the compliance period are recognized as incurred to selling, general and administrative expense.The assets and liabilities of our consolidated VIEs were $140.9 million and $104.2 million, respectively, as of December 31, 2014 and 2013.The assets of the VIEs serve as the sole source of repayment for the debt issued by these entities. US Bank does not have recourse to us or our other assets, with the exception of customary representations and indemnities we have provided. We are not required and do not currently intend to provide additional financial support to these VIEs. While these subsidiaries are included in our consolidated financial statements, these subsidiaries are separate legal entities and their assets are legally owned by them and not available to our creditors. |

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| - Definition
The entire disclosure for noncontrolling interest in consolidated subsidiaries, which could include the name of the subsidiary, the ownership percentage held by the parent, the ownership percentage held by the noncontrolling owners, the amount of the noncontrolling interest, the location of this amount on the balance sheet (when not reported separately), an explanation of the increase or decrease in the amount of the noncontrolling interest, the noncontrolling interest share of the net Income or Loss of the subsidiary, the location of this amount on the income statement (when not reported separately), the nature of the noncontrolling interest such as background information and terms, the amount of the noncontrolling interest represented by preferred stock, a description of the preferred stock, and the dividend requirements of the preferred stock.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.31) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=18733093&loc=SL4573702-111684
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