XML 97 R81.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Shareholders' Equity (Share Repurchases) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 12 Months Ended
--- | ---
Dec. 27, 2017 | Dec. 28, 2016 | Dec. 30, 2015
Equity, Class of Treasury Stock [Line Items] |  |  |
Common stock shares repurchased during the period (shares) | 6,800 | 4,580 | 8,500
Common stock shares repurchased during the period (value in US$) | $ 82,858 | $ 51,771 | $ 92,676
Share Repurchase Program 2017 [Member] |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |
Share repurchase, authorized amount (dollars) | 200,000 |  |
Remaining shares to be repurchased (value in US$) | 196,300 |  |
Share Repurchase Program 2016 [Member] |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |
Share repurchase, authorized amount (dollars) | 100,000 |  |
Share Repurchase Program 2015 [Member] |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |
Share repurchase, authorized amount (dollars) | $ 100,000 |  |
November 2015 Accelerated Share Repurchase [Member] |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |
Share repurchase, authorized amount (dollars) |  |  | $ 50,000
Common stock shares repurchased during the period (shares) |  | 1,500 | 3,500
Volume-weighted average price |  | $ 9.90 |
Common stock shares repurchased during the period (value in US$) |  | $ 13,100 | $ 36,900
Remaining shares to be repurchased (value in US$) |  |  | $ 13,100
November 2016 Accelerated Share Repurchase [Member] |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |
Share repurchase, authorized amount (dollars) |  | $ 25,000 |
Common stock shares repurchased during the period (shares) | 500 | 1,500 |
Volume-weighted average price | $ 12.36 |  |
Common stock shares repurchased during the period (value in US$) | $ 6,900 | $ 18,100 |
Remaining shares to be repurchased (value in US$) |  | $ 6,900 |

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_EquityClassOfTreasuryStockLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of stock repurchase plan authorized. + References No definition available. + Details
Name: | us-gaap_StockRepurchaseProgramAuthorizedAmount1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount remaining of a stock repurchase plan authorized. + References No definition available. + Details
Name: | us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Total cost of shares repurchased divided by the total number of shares repurchased. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 + Details
Name: | us-gaap_TreasuryStockAcquiredAverageCostPerShare
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of shares that have been repurchased during the period and are being held in treasury. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 2: 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(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644 + Details
Name: | us-gaap_TreasuryStockSharesAcquired
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
Name: | us-gaap_TreasuryStockValueAcquiredCostMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_ShareRepurchaseProgramAxis=denn_ShareRepurchaseProgram2017Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShareRepurchaseProgramAxis=denn_ShareRepurchaseProgram2016Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShareRepurchaseProgramAxis=denn_ShareRepurchaseProgram2015Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShareRepurchaseProgramAxis=denn_November2015AcceleratedShareRepurchaseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShareRepurchaseProgramAxis=denn_November2016AcceleratedShareRepurchaseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |