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Stock-based Compensation Plans (Schedule of Shared-Based Compensation, Performance Units (Details) | 3 Months Ended | 12 Months Ended
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Dec. 31, 2017 shares | Mar. 31, 2017 shares | Dec. 31, 2016 shares | Dec. 31, 2015 shares | Dec. 31, 2014 shares | Dec. 31, 2013 shares | Sep. 30, 2021 shares | Sep. 30, 2020 shares | Sep. 30, 2019 shares | Sep. 30, 2018 $ / shares shares | Sep. 30, 2017 $ / shares shares | Sep. 30, 2016 $ / shares shares | Sep. 30, 2015 $ / shares shares | Sep. 30, 2014 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period |  |  |  |  |  |  |  |  |  |  | 160,063 |  |  |
Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period |  |  |  |  |  |  |  |  |  | 86,516 |  | 335,998 |  |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  |  |  | 146,061 | 263,410 |  |  |
Share-based Compensation Award, Tranche One [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | 57,092 |  |  |  |  |  |  |  |  |  |  |  |  |
2014 [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value | $ / shares |  |  |  |  |  |  |  |  |  |  |  | $ 9.38 | $ 9.78 | $ 8.52
2014 [Member] | Share-based Compensation Award, Tranche One [Member] | Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Performance Factor |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.000
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  |  |  |  | 172,880 |  |  |
2014 [Member] | Share-based Compensation Award, Tranche One [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  |  |  |  |  |  |  |  |  |  |  | 90,841
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  |  |  |  |  |  | (4,401)
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  |  |  |  | 86,440 |  |  |
2014 [Member] | Share-based Compensation Award, Tranche Two [Member] | Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Performance Factor |  |  |  |  |  |  |  |  |  |  |  |  | 0.000 |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  |  |  |  | 0 |  |  |
2014 [Member] | Share-based Compensation Award, Tranche Two [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  |  |  | 90,841 |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  |  |  |  |  | (4,401) |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  |  |  |  | 86,440 |  |  |
2014 [Member] | Share-based Compensation Award, Tranche Three [Member] | Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Performance Factor |  |  |  |  |  |  |  |  |  |  |  | 1.021 |  |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  |  |  |  | 85,199 |  |  |
2014 [Member] | Share-based Compensation Award, Tranche Three [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  |  |  | 90,849 |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  |  |  |  | (7,402) |  |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  |  |  |  | 83,447 |  |  |
2015 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value | $ / shares |  |  |  |  |  |  |  |  |  |  | $ 13.26 |  |  |
2015 [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value | $ / shares |  |  |  |  |  |  |  |  |  |  |  | $ 9.38 | $ 9.78 |
2015 [Member] | Share-based Compensation Award, Tranche One [Member] | Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Performance Factor |  |  |  |  |  |  |  |  |  |  |  |  | 0.000 |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  |  |  | 0 |  |  |  |
2015 [Member] | Share-based Compensation Award, Tranche One [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  |  | 80,233 |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  |  |  |  |  | (3,835) |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  |  |  | 76,398 |  |  |  |
2015 [Member] | Share-based Compensation Award, Tranche Two [Member] | Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Performance Factor |  |  |  |  |  |  |  |  |  |  |  | 1.021 |  |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  |  |  | 75,327 |  |  |  |
2015 [Member] | Share-based Compensation Award, Tranche Two [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  |  | 80,229 |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  |  |  |  | (6,447) |  |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  |  |  | 73,782 |  |  |  |
2015 [Member] | Share-based Compensation Award, Tranche Three [Member] | Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Performance Factor |  |  |  |  |  |  |  |  |  |  | 1.000 |  |  |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  |  |  | 68,556 |  |  |  |
2015 [Member] | Share-based Compensation Award, Tranche Three [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  |  | 80,229 |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  |  |  | (11,673) |  |  |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  |  |  | 68,556 |  |  |  |
2016 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value | $ / shares |  |  |  |  |  |  |  |  |  | $ 12.50 | $ 13.26 |  |  |
2016 [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value | $ / shares |  |  |  |  |  |  |  |  |  |  |  | $ 9.38 |  |
2016 [Member] | Share-based Compensation Award, Tranche One [Member] | Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Performance Factor |  |  |  |  |  |  |  |  |  |  |  | 1.021 |  |
2016 [Member] | Share-based Compensation Award, Tranche One [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  | 77,823 |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  |  |  |  | (3,998) |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  |  |  |  |  |  |  |  |  |  |  | 73,825 |  |
2016 [Member] | Share-based Compensation Award, Tranche Two [Member] | Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Performance Factor |  |  |  |  |  |  |  |  |  |  | 1.000 |  |  |
2016 [Member] | Share-based Compensation Award, Tranche Two [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  | 77,824 |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  |  |  | (3,997) |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  |  |  |  |  |  |  |  |  |  | 73,827 |  |  |
2016 [Member] | Share-based Compensation Award, Tranche Three [Member] | Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Performance Factor |  |  |  |  |  |  |  |  |  | 1.357 |  |  |  |
2016 [Member] | Share-based Compensation Award, Tranche Three [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  | 77,824 |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  |  | (61,841) |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  |  |  |  |  |  |  |  |  | 15,983 |  |  |  |
2017 member [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value | $ / shares |  |  |  |  |  |  |  |  |  | $ 12.50 | $ 13.26 |  |  |
2017 member [Member] | Share-based Compensation Award, Tranche One [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Performance Factor |  |  |  |  |  |  |  |  |  |  | 1.000 |  |  |
2017 member [Member] | Share-based Compensation Award, Tranche One [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  | 59,285 |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  |  |  | (5,279) |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  |  |  |  |  |  |  |  |  |  | 54,006 |  |  |
2017 member [Member] | Share-based Compensation Award, Tranche Two [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Performance Factor |  |  |  |  |  |  |  |  |  | 1.357 |  |  |  |
2017 member [Member] | Share-based Compensation Award, Tranche Two [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  | 59,286 |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  |  | (39,910) |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  |  |  |  |  |  |  |  |  | 19,376 |  |  |  |
2017 member [Member] | Share-based Compensation Award, Tranche Three [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  | 59,290 |  |  |  |  |  |  |  |  |  |  |
January 23, 2017 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value | $ / shares |  |  |  |  |  |  |  |  |  |  | $ 13.15 |  |  |
January 23, 2017 [Member] | Share-based Compensation Award, Tranche One [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Performance Factor |  |  |  |  |  |  |  |  |  |  | 1.000 |  |  |
January 23, 2017 [Member] | Share-based Compensation Award, Tranche One [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  | 19,012 |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  |  |  | 0 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  |  |  |  |  |  |  |  |  |  | 19,012 |  |  |
January 23, 2017 [Member] | Share-based Compensation Award, Tranche Two [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Performance Factor |  |  |  |  |  |  |  |  |  | 1.357 |  |  |  |
January 23, 2017 [Member] | Share-based Compensation Award, Tranche Two [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  | 19,011 |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  |  | 0 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  |  |  |  |  |  |  |  |  | 19,011 |  |  |  |
January 23, 2017 [Member] | Share-based Compensation Award, Tranche Three [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  | 19,011 |  |  |  |  |  |  |  |  |  |  |  |
November 28, 2017 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value | $ / shares |  |  |  |  |  |  |  |  |  | $ 12.50 |  |  |  |
November 28, 2017 [Member] | Share-based Compensation Award, Tranche One [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Performance Factor |  |  |  |  |  |  |  |  |  | 1.357 |  |  |  |
November 28, 2017 [Member] | Share-based Compensation Award, Tranche One [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  |  |  |  |  |  |  | 57,092 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  |  | 0 |  |  |  |
November 28, 2017 [Member] | Share-based Compensation Award, Tranche Two [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | 57,092 |  |  |  |  |  |  |  |  |  |  |  |  |
November 28, 2017 [Member] | Share-based Compensation Award, Tranche Three [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | 57,104 |  |  |  |  |  |  |  |  |  |  |  |  |
Scenario, Forecast [Member] | 2016 [Member] | Share-based Compensation Award, Tranche One [Member] | Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  |  | 75,375 |  |  |  |  |
Scenario, Forecast [Member] | 2016 [Member] | Share-based Compensation Award, Tranche Two [Member] | Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  |  | 73,827 |  |  |  |  |
Scenario, Forecast [Member] | 2016 [Member] | Share-based Compensation Award, Tranche Three [Member] | Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  |  | 21,689 |  |  |  |  |
Scenario, Forecast [Member] | 2017 member [Member] | Share-based Compensation Award, Tranche One [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  | 54,006 |  |  |  |  |  |
Scenario, Forecast [Member] | 2017 member [Member] | Share-based Compensation Award, Tranche Two [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  | 26,294 |  |  |  |  |  |
Scenario, Forecast [Member] | 2017 member [Member] | Share-based Compensation Award, Tranche Three [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  | (39,909) |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  |  |  |  |  |  |  |  | 19,381 |  |  |  |  |
Scenario, Forecast [Member] | January 23, 2017 [Member] | Share-based Compensation Award, Tranche One [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  | 19,012 |  |  |  |  |  |
Scenario, Forecast [Member] | January 23, 2017 [Member] | Share-based Compensation Award, Tranche Two [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  |  | 25,798 |  |  |  |  |  |
Scenario, Forecast [Member] | January 23, 2017 [Member] | Share-based Compensation Award, Tranche Two [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  |  |  |  |  |  |  |  | 19,011 |  |  |  |  |
Scenario, Forecast [Member] | January 23, 2017 [Member] | Share-based Compensation Award, Tranche Three [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  | 0 |  |  |  |  |
Scenario, Forecast [Member] | November 28, 2017 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  |  |  |  |  | 57,104 | 57,092 |  |  |  |  |
Scenario, Forecast [Member] | November 28, 2017 [Member] | Share-based Compensation Award, Tranche One [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Settlement of performance-based restricted stock units, net of shares withheld for taxes |  |  |  |  |  |  | 77,474 |  |  |  |  |  |  |
Scenario, Forecast [Member] | November 27, 2018 [Member] | Share-based Compensation Award, Tranche Two [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  |  | 0 |  |  |  |  |
Scenario, Forecast [Member] | November 27, 2018 [Member] | Share-based Compensation Award, Tranche Three [Member] | PRSU base units [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period |  |  |  |  |  |  |  | 0 |  |  |  |  |  |

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